Let’s go step by step to solve the “Precision Problems” section.
We are given measurements from 7 teams:
Team 1: 2.65 cm
Team 2: 2.75 cm
Team 3: 2.80 cm
Team 4: 2.77 cm
Team 5: 2.60 cm
Team 6: 2.65 cm
Team 7: 2.68 cm
---
Step 1: Find the average (mean) length
Add all the values together:
2.65 + 2.75 = 5.40
5.40 + 2.80 = 8.20
8.20 + 2.77 = 10.97
10.97 + 2.60 = 13.57
13.57 + 2.65 = 16.22
16.22 + 2.68 =
18.90
Total sum = 18.90 cm
Number of teams = 7
Average = 18.90 ÷ 7 = ?
Let’s divide:
7 × 2.7 = 18.9 → So, 18.90 ÷ 7 =
2.70 cm
✔ Average length =
2.70 cm
---
Step 2: Subtract the highest value from the lowest value (range)
Look at the data:
Lowest value = Team 5:
2.60 cm
Highest value = Team 3:
2.80 cm
Range = 2.80 - 2.60 =
0.20 cm
✔ Range =
0.20 cm
---
Step 3: Divide this number by 2
0.20 ÷ 2 =
0.10 cm
This is the approximate ± range from the average.
✔ Half-range =
0.10 cm
---
Step 4: Show precision as average ± range
So, precision = average ± half-range =
2.70 ± 0.10 cm
✔ Final precision expression:
2.70 ± 0.10 cm
---
Now let’s fill in the blanks in order:
- The average length is
2.70 cm.
- Subtract the highest value from the lowest value:
0.20 cm.
- Divide this number by 2:
0.10 cm.
- The precision of the measurement was
2.70 ±
0.10 cm.
──────────────────────────────────────
Final Answer:
The average length is 2.70 cm.
Subtract the highest value from the lowest value: 0.20 cm.
Divide this number by 2: 0.10 cm.
The precision of the measurement was 2.70 ± 0.10 cm.
Parent Tip: Review the logic above to help your child master the concept of accuracy vs precision worksheet.
