This worksheet provides three real-world scenarios, including test scores and weather data, for students to practice calculating statistical measures.

Let’s solve each problem step by step. We’ll find the mean, median, mode, and range for each set of numbers.

---

Problem 1: Test Scores

Scores: 25, 17, 21, 25, 23, 21, 27, 21, 18
Total children = 9

#### Step 1: Mean (average)
Add all scores:
25 + 17 = 42
42 + 21 = 63
63 + 25 = 88
88 + 23 = 111
111 + 21 = 132
132 + 27 = 159
159 + 21 = 180
180 + 18 = 198

Divide by number of scores (9):
198 ÷ 9 = 22

✔ Mean = 22

#### Step 2: Median (middle value when ordered)
First, order the scores from smallest to largest:
17, 18, 21, 21, 21, 23, 25, 25, 27

There are 9 numbers → middle is the 5th one.
Count: 1st=17, 2nd=18, 3rd=21, 4th=21, 5th=21

✔ Median = 21

#### Step 3: Mode (most frequent)
Look at how many times each score appears:
- 17: once
- 18: once
- 21: three times ← most!
- 23: once
- 25: twice
- 27: once

✔ Mode = 21

#### Step 4: Range (biggest - smallest)
Biggest = 27
Smallest = 17
27 - 17 = 10

✔ Range = 10

---

Problem 2: Salamander Jumps

Jumps: Captain 2.3m, Sally 3.5m, Quadra 1.7m, Tyger 4.3m, Frazer 2.1m, Quadra 1.7m
So list: 2.3, 3.5, 1.7, 4.3, 2.1, 1.7
Total jumps = 6

#### Step 1: Mean
Add them:
2.3 + 3.5 = 5.8
5.8 + 1.7 = 7.5
7.5 + 4.3 = 11.8
11.8 + 2.1 = 13.9
13.9 + 1.7 = 15.6

Divide by 6:
15.6 ÷ 6 = 2.6

✔ Mean = 2.6 m

#### Step 2: Median
Order the numbers:
1.7, 1.7, 2.1, 2.3, 3.5, 4.3

Even number of values → average of 3rd and 4th
3rd = 2.1, 4th = 2.3
(2.1 + 2.3) ÷ 2 = 4.4 ÷ 2 = 2.2

✔ Median = 2.2 m

#### Step 3: Mode
Which number appears most?
1.7 appears twice → others appear once
✔ Mode = 1.7 m

#### Step 4: Range
Biggest = 4.3
Smallest = 1.7
4.3 - 1.7 = 2.6

✔ Range = 2.6 m

---

Problem 3: Temperatures

Temperatures:
Amsterdam 5°C, Hong Kong 15°C, Moscow -17°C, Toronto -17°C, Cape Town 20°C, Minneapolis -21°C, New York -6°C
List: 5, 15, -17, -17, 20, -21, -6
Total places = 7

#### Step 1: Mean
Add all temperatures:
Start with positives: 5 + 15 + 20 = 40
Negatives: -17 + (-17) + (-21) + (-6) = let’s add absolute values first: 17+17+21+6 = 61 → so total negative = -61
Now: 40 + (-61) = -21

Divide by 7:
-21 ÷ 7 = -3

✔ Mean = -3°C

#### Step 2: Median
Order from coldest to warmest:
-21, -17, -17, -6, 5, 15, 20

7 numbers → middle is 4th one
Count: 1st=-21, 2nd=-17, 3rd=-17, 4th=-6

✔ Median = -6°C

#### Step 3: Mode
Which temperature appears most?
-17 appears twice → others appear once
✔ Mode = -17°C

#### Step 4: Range
Warmest = 20°C
Coldest = -21°C
Range = 20 - (-21) = 20 + 21 = 41

✔ Range = 41°C

---

Final Answer:

Problem 1:
Mean = 22, Median = 21, Mode = 21, Range = 10

Problem 2:
Mean = 2.6, Median = 2.2, Mode = 1.7, Range = 2.6

Problem 3:
Mean = -3, Median = -6, Mode = -17, Range = 41