Conversion factors and changing units
Answers are for parents and teachers.
1
Write the conversion factor for minutes and hours, then change 3.5 h into minutes.
60 min : 1 h. 3.5 × 60 = 210 min.
2
Change 0.4 km into metres and 6,500 mL into litres.
0.4 × 1,000 = 400 m. 6,500 ÷ 1,000 = 6.5 L.
3
A rope is 2.3 m long and a second rope is 215 cm long. Which is longer and by how many cm?
2.3 m = 230 cm. The first rope is longer by 230 − 215 = 15 cm.
4
A microbus goes 90 km/h. Write its speed in m/s.
90 × 1,000 ÷ 3,600 = 25 m/s.
5
Karim says: “To change grams into kilograms I multiply by 1,000.” Is he right? Show the right way with 4,200 g.
No. A kilogram is larger, so the number must shrink: 4,200 ÷ 1,000 = 4.2 kg.