Question

exercise 2.5
round to the nearest whole number.

1. 29.05 2. 135.9 3. 0.4

round to the nearest tenth place.

1. 20.045 5. 0.98 6. 200.03

round to the nearest hundredth place.

1. 1.234 8. 0.976 9. 345.095

round to the nearest thousandth place.

1. 3 11. 1,367.0982 12. 0.9855

Explanation:

Step1: Round 29.05 to whole number

Look at tenths digit (0 < 5), keep whole number: $29$

Step2: Round 135.9 to whole number

Look at tenths digit (9 ≥ 5), add 1 to whole number: $135 + 1 = 136$

Step3: Round 0.4 to whole number

Look at tenths digit (4 < 5), keep whole number: $0$

Step4: Round 20.045 to nearest tenth

Look at hundredths digit (4 < 5), keep tenths digit: $20.0$

Step5: Round 0.98 to nearest tenth

Look at hundredths digit (8 ≥ 5), add 1 to tenths digit: $0.9 + 0.1 = 1.0$

Step6: Round 200.03 to nearest tenth

Look at hundredths digit (3 < 5), keep tenths digit: $200.0$

Step7: Round 1.234 to nearest hundredth

Look at thousandths digit (4 < 5), keep hundredths digit: $1.23$

Step8: Round 0.976 to nearest hundredth

Look at thousandths digit (6 ≥ 5), add 1 to hundredths digit: $0.97 + 0.01 = 0.98$

Step9: Round 345.095 to nearest hundredth

Look at thousandths digit (5 ≥ 5), add 1 to hundredths digit: $345.09 + 0.01 = 345.10$

Step10: Round 3 to nearest thousandth

Add decimal zeros: $3.000$

Step11: Round 1,367.0982 to nearest thousandth

Look at ten-thousandths digit (2 < 5), keep thousandths digit: $1367.098$

Step12: Round 0.9855 to nearest thousandth

Look at ten-thousandths digit (5 ≥ 5), add 1 to thousandths digit: $0.985 + 0.001 = 0.986$

Answer:

1. 29
2. 136
3. 0
4. 20.0
5. 1.0
6. 200.0
7. 1.23
8. 0.98
9. 345.10
10. 3.000
11. 1367.098
12. 0.986