Work through these on your own. Keep your working neat: the method matters as much as the answer. Questions marked H are for Higher tier.

1.5 Rounding and estimation — Practise

Work through these on your own. Keep your working neat: the method matters as much as the answer. Questions marked H are for Higher tier.

1. Round $7\,284$ to the nearest (a) $10$, (b) $100$, (c) $1000$.
2. Round $12.78$ to 1 decimal place.
3. Round $0.916$ to 2 decimal places.
4. Round $63\,500$ to 2 significant figures.
5. Round $0.020\,45$ to 3 significant figures.
6. Estimate $59 \times 31$ by rounding each number to 1 significant figure.
7. Estimate $497 \div 5$.
8. A jug holds $1.85$ litres. Round this to the nearest tenth of a litre and to the nearest litre.
9. A journey takes $3$ hours $47$ minutes. Round this to the nearest hour.
10. A cyclist travels $24.6$ km in $1.8$ hours. Estimate the average speed by rounding, then say whether an exact answer of $13.7$ km/h is reasonable.
11. The stall's profit was £39.20. A poster must show the profit to the nearest £5. What should it say?
12. H A number rounds to $4.7$ to 1 decimal place. Write down the smallest and largest values it could have.
13. H Estimate $\dfrac{6.2 \times 19.8}{3.1}$ by rounding each number to 1 significant figure.