Work through the levels in order. Type your answer and press Check — open the worked solution if you get stuck. Answers like -6, 3/4 or 0.25 are typed exactly as shown. A ⭐ Bonus Challenge at the end is extra credit — skip it if the rest was hard work.
Level 1 · Warm-up
1 If one step is about 0.75 metres, roughly how far is 1000 steps?
Show worked solution
1000 × 0.75 = 750 m.
2 Options in a question are 60, 600, 6000 and 60 000. Write how many times bigger each option is than the one before, and whether you should estimate or calculate exactly (type estimate or calculate).
Show worked solution
Each is 10 times the one before, so they are decades apart and you should estimate.
3 Roughly how many kilometres is 7500 metres?
Show worked solution
7500 ÷ 1000 = 7.5 km.
Level 2 · Core
4 A car travels about 15 000 km a year. Roughly how far does it travel in 20 years?
Show worked solution
15 000 × 20 = 300 000 km.
5 Someone walks 7.5 km a day. Write roughly how many kilometres that is in a year (use 350 days), and roughly how many in 10 years.
Show worked solution
7.5 × 350 = 2625 km a year, and ten times that is 26250 km.
6 A distance of 1 500 000 km is about how many times around the Earth, if once around is about 40 000 km? Give your answer to the nearest whole number.
Show worked solution
1 500 000 ÷ 40 000 = 37.5, so about 38 times — which is why that option was implausible.
Level 3 · Challenge
7 A person walks 10 000 steps a day for 55 adult years, with a step of about 0.75 m.1 They walk about 7.5 km a day.
2 They walk roughly 143 000 km in total.
3 The best option of 1500, 15 000, 150 000 and 1 500 000 km is 15 000.
Which statements are correct?
2 They walk roughly 143 000 km in total.
3 The best option of 1500, 15 000, 150 000 and 1 500 000 km is 15 000.
Which statements are correct?
Show worked solution
7.5 km a day (1 ✓) × about 350 days × 55 years is roughly 143 000 km (2 ✓), which is nearest to 150 000, not 15 000 (3 ✗). 1 and 2.
8 A tap drips once every 2 seconds, and each drip is about 0.5 millilitres. Write roughly how many drips occur in an hour, and roughly how many litres that is in a day.
Show worked solution
3600 ÷ 2 = 1800 drips an hour. That is 900 mL an hour, so 24 × 900 = 21 600 mL = 21.6 litres a day.
9 A person takes about 7000 steps in an hour of walking. At 0.75 m a step, about how many kilometres is that in an hour? Give your answer to the nearest whole number.
Show worked solution
7000 × 0.75 = 5250 m, which is 5.25 km, so about 5 km.