Let's solve each problem step by step using
ratio and proportion concepts.
---
Problem 1
A playschool has 63 boys and 27 girls. What will be the number of boys if there are 9 girls in the school?
#### Step 1: Find the ratio of boys to girls.
$$
\text{Ratio of boys to girls} = \frac{63}{27} = \frac{7}{3} \quad \text{(simplify by dividing both by 9)}
$$
So, for every
3 girls, there are
7 boys.
Now, we want to find how many boys there are when there are
9 girls.
Set up a proportion:
$$
\frac{7}{3} = \frac{x}{9}
$$
Cross-multiply:
$$
7 \times 9 = 3x \Rightarrow 63 = 3x \Rightarrow x = 21
$$
✔ Answer: 21 boys
---
Problem 2
A machine can produce 6 yards of fabric in 2 minutes. How much fabric can the machine produce in 1 hour?
#### Step 1: Convert 1 hour to minutes.
$$
1 \text{ hour} = 60 \text{ minutes}
$$
#### Step 2: Find rate of production per minute.
$$
\text{In 2 minutes} \rightarrow 6 \text{ yards} \\
\text{So in 1 minute} \rightarrow \frac{6}{2} = 3 \text{ yards}
$$
#### Step 3: Multiply by 60 minutes.
$$
3 \text{ yards/minute} \times 60 = 180 \text{ yards}
$$
✔ Answer: 180 yards
---
Problem 3
12 miles are approximately equal to 19 km. How many km (approx.) are equal to 18 miles?
Set up a proportion:
$$
\frac{12 \text{ miles}}{19 \text{ km}} = \frac{18 \text{ miles}}{x \text{ km}}
$$
Cross-multiply:
$$
12x = 19 \times 18 = 342 \\
x = \frac{342}{12} = 28.5
$$
✔ Answer: 28.5 km
---
Problem 4
80 boys are attending a picnic. There is a ratio of 3:5 for the number of girls to the number of boys. How many girls are there?
The ratio
girls : boys = 3 : 5
Let number of girls = $3x$, number of boys = $5x$
But we know boys = 80:
$$
5x = 80 \Rightarrow x = 16
$$
So, number of girls = $3x = 3 \times 16 = 48$
✔ Answer: 48 girls
---
Problem 5
The total weight of 15 boxes is 45 pounds. How much would 40 boxes weigh?
First, find weight of one box:
$$
\frac{45 \text{ pounds}}{15 \text{ boxes}} = 3 \text{ pounds per box}
$$
Now, 40 boxes:
$$
40 \times 3 = 120 \text{ pounds}
$$
✔ Answer: 120 pounds
---
Problem 6
4 spoons cost $12. How much do 16 spoons cost?
Find cost per spoon:
$$
\frac{12}{4} = 3 \text{ dollars per spoon}
$$
Now, 16 spoons:
$$
16 \times 3 = 48 \text{ dollars}
$$
✔ Answer: $48
---
✔ Final Answers:
1.
21 boys
2.
180 yards
3.
28.5 km
4.
48 girls
5.
120 pounds
6.
$48
Let me know if you'd like these explained visually or with diagrams!
Parent Tip: Review the logic above to help your child master the concept of ratio and proportion worksheet 6th grade.