Math worksheet focusing on identifying the constant of proportionality in various scenarios, including graphs, tables, and word problems.
A worksheet titled "Constant of Proportionality" with five problems, each containing a graph, table, or word problem to find the constant of proportionality, with one box in each row being the odd one out to be shaded.
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Step-by-step solution for: 20+ Grade 8 Constant of Proportionality Worksheets 2024
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Show Answer Key & Explanations
Step-by-step solution for: 20+ Grade 8 Constant of Proportionality Worksheets 2024
Let's solve each row of this "Odd Man Out" worksheet step by step. The goal is to:
1. Find the constant of proportionality (k) for each box.
2. Identify which box in each row does not match the others — that’s the “odd man out.”
3. Shade or mark the one that doesn’t belong.
---
We have four boxes:
#### Box A: Graph
- Points: (1, 12), (2, 24), (3, 36)
- This is a straight line through origin → proportional.
- Constant of proportionality:
$ k = \frac{y}{x} = \frac{12}{1} = 12 $
✔ So, k = 12
#### Box B: Word Problem – Jaylin’s Earnings
- $36 for 3 hours → $36 / 3 = $12/hour
- $60 for 5 hours → $60 / 5 = $12/hour
- So, rate = $12 per hour
✔ k = 12
#### Box C: Table
| x | 12 | 24 | 60 |
|---|----|----|----|
| y | 1 | 2 | 5 |
Check ratios:
- 1/12 = 0.0833...
- 2/24 = 0.0833...
- 5/60 ≈ 0.0833...
All are equal: $ \frac{y}{x} = \frac{1}{12} $ → so k = 1/12
Wait! But earlier ones had k = 12. This is not the same.
Hold on — if k = y/x, then here k = 1/12, but others have k = 12.
So this one is different!
But let’s check again: Is it possible they meant k = x/y?
No — constant of proportionality is y = kx, so k = y/x.
Here:
- For x=12, y=1 → k = 1/12
- x=24, y=2 → k = 2/24 = 1/12
- x=60, y=5 → k = 5/60 = 1/12
So k = 1/12
But other boxes have k = 12
So this one is different.
#### Box D: Equation
- y = 12x → clearly k = 12
✔ k = 12
---
- A: k = 12
- B: k = 12
- C: k = 1/12 ← ODD MAN OUT
- D: k = 12
➡️ Shade Box C (the table)
---
#### Box A: Word Problem – Sophie’s Reading
- 4 books in 2 months → 4/2 = 2 books/month
- 10 books in 5 months → 10/5 = 2 books/month
→ Rate = 2 books per month
So, y = 2x → k = 2
But wait: Is it proportional? Yes, since rate is constant.
So k = 2
#### Box B: Table
| x | 0.1 | 2.6 | 15 |
|---|-----|-----|----|
| y | 0.1 | 2.6 | 15 |
Check ratios:
- 0.1 / 0.1 = 1
- 2.6 / 2.6 = 1
- 15 / 15 = 1
So k = 1
Wait — but we just said k = 2 from the word problem.
So this table has k = 1 → different.
But hold on — is the table consistent with y = x? Yes, because y = x → k = 1.
But the word problem has k = 2.
So conflict.
Wait — maybe I misread.
Let’s recheck:
- Sophie read 4 books in 2 months → 2 books/month → k = 2
- So if x = months, y = books → y = 2x → k = 2
But the table says: when x = 0.1, y = 0.1 → k = 1
So this table does NOT match.
So Box B is odd?
But let’s look at the rest.
#### Box C: Equation
- y = x → k = 1
✔ k = 1
#### Box D: Graph
- Points: (1,1), (2,2), (3,3), (4,4), (5,5) → y = x → k = 1
✔ k = 1
So:
- A: k = 2
- B: k = 1
- C: k = 1
- D: k = 1
So A is the odd one out
Because only A has k = 2, others have k = 1
➡️ Shade Box A (Sophie’s reading problem)
---
#### Box A: Equation
- y = (1/3)x → k = 1/3
✔ k = 1/3
#### Box B: Graph
- Points: (2,6), (4,12), (6,18), (8,24), (10,30)
- Check ratio: 6/2 = 3, 12/4 = 3, 18/6 = 3 → k = 3
So k = 3
But A has k = 1/3 → not matching
Wait — so already different.
Let’s continue.
#### Box C: Table
| x | 4 | 6 | 9 |
|---|---|---|---|
| y |12 |18 |27 |
Check:
- 12/4 = 3
- 18/6 = 3
- 27/9 = 3 → k = 3
✔ k = 3
#### Box D: Word Problem – Alexis’ Cookies
- 24 cookies with 8 tsp sugar → 8/24 = 1/3 tsp per cookie
- 45 cookies with 15 tsp sugar → 15/45 = 1/3 tsp per cookie
So sugar per cookie = 1/3 → y = (1/3)x → k = 1/3
✔ k = 1/3
So:
- A: k = 1/3
- B: k = 3
- C: k = 3
- D: k = 1/3
So two with k = 1/3 (A and D), two with k = 3 (B and C)
But the question says one odd man out.
Wait — perhaps I made a mistake.
Wait: In the graph, is it y = 3x or x = 3y?
Points: (2,6): y = 6, x = 2 → y = 3x → yes, k = 3
But the equation is y = (1/3)x → so k = 1/3
So:
- A: k = 1/3
- B: k = 3
- C: k = 3
- D: k = 1/3
So two groups: A and D → k = 1/3
B and C → k = 3
But only one should be odd.
Wait — unless I misread the graph.
Wait — the graph shows increasing values: (2,6), (4,12), etc. → y = 3x → k = 3
But A says y = (1/3)x → k = 1/3
So both A and D have k = 1/3, while B and C have k = 3
So which one is the odd one out?
Wait — maybe the equation is correct, and the graph is wrong?
No — the task is to find which one doesn't belong.
But there are two with k = 1/3 and two with k = 3.
But the instruction says: "there is an ODD MAN OUT" — meaning only one is different.
Hmm — contradiction.
Wait — let’s double-check the table.
Table: x=4, y=12 → y/x = 3
x=6, y=18 → 3
x=9, y=27 → 3 → k = 3
Graph: points show y = 3x → k = 3
Equation: y = (1/3)x → k = 1/3
Word problem: sugar per cookie = 1/3 → k = 1/3
So A and D have k = 1/3
B and C have k = 3
So no single odd one out?
But the problem says there is an odd man out.
Wait — maybe I misread the equation.
It says: y = 1/3x → which is y = (1/3)x → k = 1/3
But maybe the graph is actually inverse?
No — the graph clearly shows y increases faster than x.
(2,6): y = 3x → k = 3
But equation says k = 1/3 → so if y = (1/3)x, then when x=2, y=0.666... but graph shows y=6
So graph ≠ equation
So the equation is inconsistent with the graph.
But both the equation and word problem have k = 1/3
And graph and table have k = 3
So maybe the equation is the odd one?
Wait — no: the equation is y = 1/3x → k = 1/3
But the graph has k = 3 → so it's different.
But the word problem also has k = 1/3 → so it matches the equation.
So:
- A: y = (1/3)x → k = 1/3
- B: graph → k = 3
- C: table → k = 3
- D: word problem → k = 1/3
So A and D have k = 1/3
B and C have k = 3
So two pairs, but only one odd?
Wait — unless the graph is supposed to represent the same as the others?
But it clearly doesn’t.
Wait — maybe the equation is wrong?
Or maybe the table is wrong?
Wait — let’s look at the table:
x: 4, 6, 9
y: 12, 18, 27
This is y = 3x → k = 3
Graph: same → k = 3
Equation: y = (1/3)x → k = 1/3
Word problem: k = 1/3
So equation and word problem agree (k = 1/3)
graph and table agree (k = 3)
So both A and D are different from B and C.
But the problem says only one odd man out.
Unless I made a mistake in interpreting the word problem.
Alexis made 24 cookies with 8 tsp sugar → sugar per cookie = 8/24 = 1/3 tsp
45 cookies with 15 tsp → 15/45 = 1/3 tsp
So sugar per cookie = 1/3 → so if y = sugar, x = cookies → y = (1/3)x → k = 1/3
So correct.
Now, what about the equation? It says y = 1/3x → k = 1/3 → matches
But the graph shows y = 3x → k = 3 → does not match
The table shows y = 3x → k = 3 → does not match
So both graph and table have k = 3, while equation and word problem have k = 1/3
So either graph or table is the odd one, but they are the same.
Wait — maybe the graph is not showing y = 3x?
Let’s check the graph:
- x-axis: 2,4,6,8,10
- y-axis: 6,12,18,24,30
- Points: (2,6), (4,12), (6,18), (8,24), (10,30)
Yes → y = 3x → k = 3
So it's correct.
So the equation says y = (1/3)x → which would give (2, 0.666...) but graph shows (2,6)
So equation is wrong compared to the others.
But the word problem supports k = 1/3
So why is the equation labeled as y = 1/3x?
Wait — maybe the equation is the odd one out?
But it matches the word problem.
Unless the word problem is about cookies per sugar?
No — it says: "made 24 cookies with 8 tsp sugar"
So sugar used per cookie = 8/24 = 1/3 tsp
So if x = number of cookies, y = sugar → y = (1/3)x
So correct.
But the graph and table show y = 3x
So either the graph/table are wrong, or the equation/word problem are wrong.
But the equation and word problem both say k = 1/3
The graph and table both say k = 3
So two vs two — no odd one?
But the problem says one odd man out.
Wait — unless I misread the table.
Look at the table:
| x | 4 | 6 | 9 |
|---|---|---|---|
| y |12 |18 |27 |
Yes, y = 3x
But maybe it’s supposed to be x = 3y? No, that would be inverse.
Alternatively, maybe the constant of proportionality is defined as x/y?
No — standard is y = kx, so k = y/x
So k = 3 for table and graph
k = 1/3 for equation and word problem
So the equation and word problem are consistent, and graph and table are consistent
But only one should be odd.
Wait — maybe the equation is written incorrectly?
But it says: y = 1/3x → which is correct for the word problem.
But the graph and table are for a different scenario.
So perhaps the graph is the odd one?
But it matches the table.
Wait — unless the table is mislabeled?
No.
Wait — look at the graph: it goes from (2,6) to (10,30)
But the equation says y = (1/3)x → so at x=2, y=0.666...
But the graph shows y=6 → so it’s off by a factor of 9.
Wait — unless the graph is for x = (1/3)y?
Then y = 3x → which matches the graph.
So maybe the equation is wrong.
But it says y = 1/3x
But the word problem supports y = (1/3)x
So why is the graph showing y = 3x?
Unless the graph is for number of cookies vs sugar?
But it’s labeled as x and y, no units.
But in the table, it's x and y — no labels.
But the word problem is about sugar and cookies.
So likely, the equation and word problem are for sugar vs cookies → y = (1/3)x
The graph and table are for cookies vs sugar → y = 3x
So they are inverses.
But the constant of proportionality depends on how you define variables.
But in the table, it's x and y, and y = 3x → k = 3
In the equation, y = (1/3)x → k = 1/3
So they are different.
But the word problem supports k = 1/3
The graph and table support k = 3
So which one is the odd one?
But notice: the equation is labeled as y = 1/3x
The graph shows y = 3x
So the equation and the graph are inconsistent.
But the table also shows y = 3x
So equation is the only one with k = 1/3
But the word problem also has k = 1/3
So equation and word problem match
graph and table match
So two pairs
But the problem says one odd man out.
Wait — unless the table is the odd one?
Let’s check the table again.
x: 4, 6, 9
y: 12, 18, 27
Is this proportional? Yes, y = 3x
But look at the values: 4→12, 6→18, 9→27
But the word problem says: 24 cookies with 8 tsp sugar
So if x = sugar, y = cookies → then 8 tsp → 24 cookies → y = 3x → k = 3
Ah! Wait — maybe the word problem is about cookies per teaspoon of sugar?
Yes: 8 tsp → 24 cookies → 24/8 = 3 cookies per tsp
So y = 3x → k = 3
I think I flipped it!
Let’s re-read:
> "Alexis made 24 cookies with 8 teaspoons of sugar and 45 cookies with 15 teaspoons of sugar."
So cookies = y, sugar = x
Then:
- x = 8, y = 24 → y/x = 3
- x = 15, y = 45 → y/x = 3
So y = 3x → k = 3
Oh! I had it backward!
I thought y was sugar, but it's cookies = y, sugar = x
So k = 3
So k = 3
Similarly, the equation says y = (1/3)x → k = 1/3 → this is wrong
So now:
- A: y = (1/3)x → k = 1/3
- B: graph → y = 3x → k = 3
- C: table → y = 3x → k = 3
- D: word problem → y = 3x → k = 3
So only A has k = 1/3
Others have k = 3
➡️ Shade Box A (the equation y = 1/3x)
It's the odd one out.
---
#### Box A: Word Problem – Jazmyn’s Paint
- 2 gallons for 5 walls → 2/5 = 0.4 gallons per wall
- 4 gallons for 10 walls → 4/10 = 0.4 gallons per wall
→ So constant: 0.4 gallons/wall
So k = 0.4 = 2/5
#### Box B: Table
| x | 0.5 | 1.5 | 3.5 |
|---|-----|-----|-----|
| y | 0.2 | 0.6 | 1.4 |
Check ratios:
- 0.2 / 0.5 = 0.4
- 0.6 / 1.5 = 0.4
- 1.4 / 3.5 = 0.4
So k = 0.4 = 2/5
✔ k = 2/5
#### Box C: Graph
- Points: (2,5), (4,10), (6,15), (8,20), (10,25)
- y/x = 5/2 = 2.5, 10/4 = 2.5, etc. → k = 2.5 = 5/2
Wait — this is not 0.4
So k = 2.5
But others have k = 0.4
So this is different.
#### Box D: Equation
- y = 2/5x → k = 2/5 = 0.4
✔ k = 0.4
So:
- A: k = 0.4
- B: k = 0.4
- C: k = 2.5
- D: k = 0.4
So C (graph) is the odd one out
➡️ Shade Box C (the graph)
---
#### Box A: Table
| x | 1 | 2 | 3 |
|---|---|---|---|
| y |1.2|2.4|3.6|
Check:
- 1.2/1 = 1.2
- 2.4/2 = 1.2
- 3.6/3 = 1.2 → k = 1.2
But the equation says y = 1.25x → k = 1.25
So not matching.
But let’s see.
#### Box B: Equation
- y = 1.25x → k = 1.25
#### Box C: Word Problem – Grapes
- 4 lbs cost $5 → $5/4 = $1.25/lb
- 7 lbs cost $8.75 → $8.75/7 = ?
8.75 ÷ 7 = 1.25 → yes, $1.25 per pound
So k = 1.25
#### Box D: Graph
- Points: (4,5), (8,10), (12,15), (16,20), (20,25)
- y/x = 5/4 = 1.25, 10/8 = 1.25, etc. → k = 1.25
So:
- A: k = 1.2
- B: k = 1.25
- C: k = 1.25
- D: k = 1.25
So A (table) has k = 1.2, others have k = 1.25
➡️ Shade Box A (the table)
---
| Row | Odd Man Out | Reason |
|-----|-------------|--------|
| 1 | Table (x,y) | k = 1/12 vs others k = 12 |
| 2 | Sophie’s reading | k = 2 vs others k = 1 |
| 3 | Equation y = 1/3x | k = 1/3 vs others k = 3 |
| 4 | Graph | k = 2.5 vs others k = 0.4 |
| 5 | Table (x,y) | k = 1.2 vs others k = 1.25 |
---
- Row 1: Shade the table (third box)
- Row 2: Shade the word problem (first box)
- Row 3: Shade the equation (first box)
- Row 4: Shade the graph (third box)
- Row 5: Shade the table (first box)
Let me know if you want a visual guide!
1. Find the constant of proportionality (k) for each box.
2. Identify which box in each row does not match the others — that’s the “odd man out.”
3. Shade or mark the one that doesn’t belong.
---
🔹 Row 1
We have four boxes:
#### Box A: Graph
- Points: (1, 12), (2, 24), (3, 36)
- This is a straight line through origin → proportional.
- Constant of proportionality:
$ k = \frac{y}{x} = \frac{12}{1} = 12 $
✔ So, k = 12
#### Box B: Word Problem – Jaylin’s Earnings
- $36 for 3 hours → $36 / 3 = $12/hour
- $60 for 5 hours → $60 / 5 = $12/hour
- So, rate = $12 per hour
✔ k = 12
#### Box C: Table
| x | 12 | 24 | 60 |
|---|----|----|----|
| y | 1 | 2 | 5 |
Check ratios:
- 1/12 = 0.0833...
- 2/24 = 0.0833...
- 5/60 ≈ 0.0833...
All are equal: $ \frac{y}{x} = \frac{1}{12} $ → so k = 1/12
Wait! But earlier ones had k = 12. This is not the same.
Hold on — if k = y/x, then here k = 1/12, but others have k = 12.
So this one is different!
But let’s check again: Is it possible they meant k = x/y?
No — constant of proportionality is y = kx, so k = y/x.
Here:
- For x=12, y=1 → k = 1/12
- x=24, y=2 → k = 2/24 = 1/12
- x=60, y=5 → k = 5/60 = 1/12
So k = 1/12
But other boxes have k = 12
So this one is different.
#### Box D: Equation
- y = 12x → clearly k = 12
✔ k = 12
---
✔ Conclusion for Row 1:
- A: k = 12
- B: k = 12
- C: k = 1/12 ← ODD MAN OUT
- D: k = 12
➡️ Shade Box C (the table)
---
🔹 Row 2
#### Box A: Word Problem – Sophie’s Reading
- 4 books in 2 months → 4/2 = 2 books/month
- 10 books in 5 months → 10/5 = 2 books/month
→ Rate = 2 books per month
So, y = 2x → k = 2
But wait: Is it proportional? Yes, since rate is constant.
So k = 2
#### Box B: Table
| x | 0.1 | 2.6 | 15 |
|---|-----|-----|----|
| y | 0.1 | 2.6 | 15 |
Check ratios:
- 0.1 / 0.1 = 1
- 2.6 / 2.6 = 1
- 15 / 15 = 1
So k = 1
Wait — but we just said k = 2 from the word problem.
So this table has k = 1 → different.
But hold on — is the table consistent with y = x? Yes, because y = x → k = 1.
But the word problem has k = 2.
So conflict.
Wait — maybe I misread.
Let’s recheck:
- Sophie read 4 books in 2 months → 2 books/month → k = 2
- So if x = months, y = books → y = 2x → k = 2
But the table says: when x = 0.1, y = 0.1 → k = 1
So this table does NOT match.
So Box B is odd?
But let’s look at the rest.
#### Box C: Equation
- y = x → k = 1
✔ k = 1
#### Box D: Graph
- Points: (1,1), (2,2), (3,3), (4,4), (5,5) → y = x → k = 1
✔ k = 1
So:
- A: k = 2
- B: k = 1
- C: k = 1
- D: k = 1
So A is the odd one out
Because only A has k = 2, others have k = 1
➡️ Shade Box A (Sophie’s reading problem)
---
🔹 Row 3
#### Box A: Equation
- y = (1/3)x → k = 1/3
✔ k = 1/3
#### Box B: Graph
- Points: (2,6), (4,12), (6,18), (8,24), (10,30)
- Check ratio: 6/2 = 3, 12/4 = 3, 18/6 = 3 → k = 3
So k = 3
But A has k = 1/3 → not matching
Wait — so already different.
Let’s continue.
#### Box C: Table
| x | 4 | 6 | 9 |
|---|---|---|---|
| y |12 |18 |27 |
Check:
- 12/4 = 3
- 18/6 = 3
- 27/9 = 3 → k = 3
✔ k = 3
#### Box D: Word Problem – Alexis’ Cookies
- 24 cookies with 8 tsp sugar → 8/24 = 1/3 tsp per cookie
- 45 cookies with 15 tsp sugar → 15/45 = 1/3 tsp per cookie
So sugar per cookie = 1/3 → y = (1/3)x → k = 1/3
✔ k = 1/3
So:
- A: k = 1/3
- B: k = 3
- C: k = 3
- D: k = 1/3
So two with k = 1/3 (A and D), two with k = 3 (B and C)
But the question says one odd man out.
Wait — perhaps I made a mistake.
Wait: In the graph, is it y = 3x or x = 3y?
Points: (2,6): y = 6, x = 2 → y = 3x → yes, k = 3
But the equation is y = (1/3)x → so k = 1/3
So:
- A: k = 1/3
- B: k = 3
- C: k = 3
- D: k = 1/3
So two groups: A and D → k = 1/3
B and C → k = 3
But only one should be odd.
Wait — unless I misread the graph.
Wait — the graph shows increasing values: (2,6), (4,12), etc. → y = 3x → k = 3
But A says y = (1/3)x → k = 1/3
So both A and D have k = 1/3, while B and C have k = 3
So which one is the odd one out?
Wait — maybe the equation is correct, and the graph is wrong?
No — the task is to find which one doesn't belong.
But there are two with k = 1/3 and two with k = 3.
But the instruction says: "there is an ODD MAN OUT" — meaning only one is different.
Hmm — contradiction.
Wait — let’s double-check the table.
Table: x=4, y=12 → y/x = 3
x=6, y=18 → 3
x=9, y=27 → 3 → k = 3
Graph: points show y = 3x → k = 3
Equation: y = (1/3)x → k = 1/3
Word problem: sugar per cookie = 1/3 → k = 1/3
So A and D have k = 1/3
B and C have k = 3
So no single odd one out?
But the problem says there is an odd man out.
Wait — maybe I misread the equation.
It says: y = 1/3x → which is y = (1/3)x → k = 1/3
But maybe the graph is actually inverse?
No — the graph clearly shows y increases faster than x.
(2,6): y = 3x → k = 3
But equation says k = 1/3 → so if y = (1/3)x, then when x=2, y=0.666... but graph shows y=6
So graph ≠ equation
So the equation is inconsistent with the graph.
But both the equation and word problem have k = 1/3
And graph and table have k = 3
So maybe the equation is the odd one?
Wait — no: the equation is y = 1/3x → k = 1/3
But the graph has k = 3 → so it's different.
But the word problem also has k = 1/3 → so it matches the equation.
So:
- A: y = (1/3)x → k = 1/3
- B: graph → k = 3
- C: table → k = 3
- D: word problem → k = 1/3
So A and D have k = 1/3
B and C have k = 3
So two pairs, but only one odd?
Wait — unless the graph is supposed to represent the same as the others?
But it clearly doesn’t.
Wait — maybe the equation is wrong?
Or maybe the table is wrong?
Wait — let’s look at the table:
x: 4, 6, 9
y: 12, 18, 27
This is y = 3x → k = 3
Graph: same → k = 3
Equation: y = (1/3)x → k = 1/3
Word problem: k = 1/3
So equation and word problem agree (k = 1/3)
graph and table agree (k = 3)
So both A and D are different from B and C.
But the problem says only one odd man out.
Unless I made a mistake in interpreting the word problem.
Alexis made 24 cookies with 8 tsp sugar → sugar per cookie = 8/24 = 1/3 tsp
45 cookies with 15 tsp → 15/45 = 1/3 tsp
So sugar per cookie = 1/3 → so if y = sugar, x = cookies → y = (1/3)x → k = 1/3
So correct.
Now, what about the equation? It says y = 1/3x → k = 1/3 → matches
But the graph shows y = 3x → k = 3 → does not match
The table shows y = 3x → k = 3 → does not match
So both graph and table have k = 3, while equation and word problem have k = 1/3
So either graph or table is the odd one, but they are the same.
Wait — maybe the graph is not showing y = 3x?
Let’s check the graph:
- x-axis: 2,4,6,8,10
- y-axis: 6,12,18,24,30
- Points: (2,6), (4,12), (6,18), (8,24), (10,30)
Yes → y = 3x → k = 3
So it's correct.
So the equation says y = (1/3)x → which would give (2, 0.666...) but graph shows (2,6)
So equation is wrong compared to the others.
But the word problem supports k = 1/3
So why is the equation labeled as y = 1/3x?
Wait — maybe the equation is the odd one out?
But it matches the word problem.
Unless the word problem is about cookies per sugar?
No — it says: "made 24 cookies with 8 tsp sugar"
So sugar used per cookie = 8/24 = 1/3 tsp
So if x = number of cookies, y = sugar → y = (1/3)x
So correct.
But the graph and table show y = 3x
So either the graph/table are wrong, or the equation/word problem are wrong.
But the equation and word problem both say k = 1/3
The graph and table both say k = 3
So two vs two — no odd one?
But the problem says one odd man out.
Wait — unless I misread the table.
Look at the table:
| x | 4 | 6 | 9 |
|---|---|---|---|
| y |12 |18 |27 |
Yes, y = 3x
But maybe it’s supposed to be x = 3y? No, that would be inverse.
Alternatively, maybe the constant of proportionality is defined as x/y?
No — standard is y = kx, so k = y/x
So k = 3 for table and graph
k = 1/3 for equation and word problem
So the equation and word problem are consistent, and graph and table are consistent
But only one should be odd.
Wait — maybe the equation is written incorrectly?
But it says: y = 1/3x → which is correct for the word problem.
But the graph and table are for a different scenario.
So perhaps the graph is the odd one?
But it matches the table.
Wait — unless the table is mislabeled?
No.
Wait — look at the graph: it goes from (2,6) to (10,30)
But the equation says y = (1/3)x → so at x=2, y=0.666...
But the graph shows y=6 → so it’s off by a factor of 9.
Wait — unless the graph is for x = (1/3)y?
Then y = 3x → which matches the graph.
So maybe the equation is wrong.
But it says y = 1/3x
But the word problem supports y = (1/3)x
So why is the graph showing y = 3x?
Unless the graph is for number of cookies vs sugar?
But it’s labeled as x and y, no units.
But in the table, it's x and y — no labels.
But the word problem is about sugar and cookies.
So likely, the equation and word problem are for sugar vs cookies → y = (1/3)x
The graph and table are for cookies vs sugar → y = 3x
So they are inverses.
But the constant of proportionality depends on how you define variables.
But in the table, it's x and y, and y = 3x → k = 3
In the equation, y = (1/3)x → k = 1/3
So they are different.
But the word problem supports k = 1/3
The graph and table support k = 3
So which one is the odd one?
But notice: the equation is labeled as y = 1/3x
The graph shows y = 3x
So the equation and the graph are inconsistent.
But the table also shows y = 3x
So equation is the only one with k = 1/3
But the word problem also has k = 1/3
So equation and word problem match
graph and table match
So two pairs
But the problem says one odd man out.
Wait — unless the table is the odd one?
Let’s check the table again.
x: 4, 6, 9
y: 12, 18, 27
Is this proportional? Yes, y = 3x
But look at the values: 4→12, 6→18, 9→27
But the word problem says: 24 cookies with 8 tsp sugar
So if x = sugar, y = cookies → then 8 tsp → 24 cookies → y = 3x → k = 3
Ah! Wait — maybe the word problem is about cookies per teaspoon of sugar?
Yes: 8 tsp → 24 cookies → 24/8 = 3 cookies per tsp
So y = 3x → k = 3
I think I flipped it!
Let’s re-read:
> "Alexis made 24 cookies with 8 teaspoons of sugar and 45 cookies with 15 teaspoons of sugar."
So cookies = y, sugar = x
Then:
- x = 8, y = 24 → y/x = 3
- x = 15, y = 45 → y/x = 3
So y = 3x → k = 3
Oh! I had it backward!
I thought y was sugar, but it's cookies = y, sugar = x
So k = 3
So k = 3
Similarly, the equation says y = (1/3)x → k = 1/3 → this is wrong
So now:
- A: y = (1/3)x → k = 1/3
- B: graph → y = 3x → k = 3
- C: table → y = 3x → k = 3
- D: word problem → y = 3x → k = 3
So only A has k = 1/3
Others have k = 3
➡️ Shade Box A (the equation y = 1/3x)
It's the odd one out.
---
🔹 Row 4
#### Box A: Word Problem – Jazmyn’s Paint
- 2 gallons for 5 walls → 2/5 = 0.4 gallons per wall
- 4 gallons for 10 walls → 4/10 = 0.4 gallons per wall
→ So constant: 0.4 gallons/wall
So k = 0.4 = 2/5
#### Box B: Table
| x | 0.5 | 1.5 | 3.5 |
|---|-----|-----|-----|
| y | 0.2 | 0.6 | 1.4 |
Check ratios:
- 0.2 / 0.5 = 0.4
- 0.6 / 1.5 = 0.4
- 1.4 / 3.5 = 0.4
So k = 0.4 = 2/5
✔ k = 2/5
#### Box C: Graph
- Points: (2,5), (4,10), (6,15), (8,20), (10,25)
- y/x = 5/2 = 2.5, 10/4 = 2.5, etc. → k = 2.5 = 5/2
Wait — this is not 0.4
So k = 2.5
But others have k = 0.4
So this is different.
#### Box D: Equation
- y = 2/5x → k = 2/5 = 0.4
✔ k = 0.4
So:
- A: k = 0.4
- B: k = 0.4
- C: k = 2.5
- D: k = 0.4
So C (graph) is the odd one out
➡️ Shade Box C (the graph)
---
🔹 Row 5
#### Box A: Table
| x | 1 | 2 | 3 |
|---|---|---|---|
| y |1.2|2.4|3.6|
Check:
- 1.2/1 = 1.2
- 2.4/2 = 1.2
- 3.6/3 = 1.2 → k = 1.2
But the equation says y = 1.25x → k = 1.25
So not matching.
But let’s see.
#### Box B: Equation
- y = 1.25x → k = 1.25
#### Box C: Word Problem – Grapes
- 4 lbs cost $5 → $5/4 = $1.25/lb
- 7 lbs cost $8.75 → $8.75/7 = ?
8.75 ÷ 7 = 1.25 → yes, $1.25 per pound
So k = 1.25
#### Box D: Graph
- Points: (4,5), (8,10), (12,15), (16,20), (20,25)
- y/x = 5/4 = 1.25, 10/8 = 1.25, etc. → k = 1.25
So:
- A: k = 1.2
- B: k = 1.25
- C: k = 1.25
- D: k = 1.25
So A (table) has k = 1.2, others have k = 1.25
➡️ Shade Box A (the table)
---
✔ Final Answers:
| Row | Odd Man Out | Reason |
|-----|-------------|--------|
| 1 | Table (x,y) | k = 1/12 vs others k = 12 |
| 2 | Sophie’s reading | k = 2 vs others k = 1 |
| 3 | Equation y = 1/3x | k = 1/3 vs others k = 3 |
| 4 | Graph | k = 2.5 vs others k = 0.4 |
| 5 | Table (x,y) | k = 1.2 vs others k = 1.25 |
---
📌 Summary of Shading:
- Row 1: Shade the table (third box)
- Row 2: Shade the word problem (first box)
- Row 3: Shade the equation (first box)
- Row 4: Shade the graph (third box)
- Row 5: Shade the table (first box)
Let me know if you want a visual guide!
Parent Tip: Review the logic above to help your child master the concept of constant of proportionality worksheet.