Checking and securing understanding of estimating through rounding

12 questions

1. Rounding means to change a number into another number that is ___ the same value but is easier to work with.
2. Round 780 257 to the nearest ten thousand.
3. Round 123.408 to 2 decimal places.
4. Round 0.01872 to 2 significant figures.
5. Truncate 74 283 to 2 significant figures.
6. Truncate 0.02078 to 3 significant figures.
7. When estimating calculations round each value to 1 ___ figure.
8. Choose the correct calculation to estimate the cost of hiring a plumber for 5.75 hours, where the total cost = £48 × number of hours + £32
9. Estimate the value of 7.236\times38.4\over1.704
10. Will the estimation of 45.87 × 763 be an overestimate or underestimate?
11. Estimate the total length of 23 bricks if each brick measures 21.5 cm.
12. Estimate the area of a circle with a diameter of 12.8 cm.

License: OGL