7.6
Inverse proportion
Homework
1
A walker travelling at an average of 6 km/h completes a journey in 4 hours. How long will it take
if the average speed is:
a 3 km/h
b 8 km/h?
2
A group of people hire a coach for a day. If 10 people share the cost it will be 48 dollars each.
How much will it cost per person if:
a 20 people share the cost
b 15 people share the cost?
3
Ayesha wants to buy some bottles of lemonade for a party. She can afford 20 bottles at $2.50
each. How many can she afford if they each cost:
a $2
b $4?
4
The cost of a taxi is being shared between some friends. If 6 people travel in the taxi it will cost
24 dollars each. How much will it cost per person if:
a 5 people travel
b 4 people travel?
5
A shelf in a shop can display 30 bottles side by side. The bottles are 8 cm wide.
How many boxes 12 cm wide can be displayed side by side on the same shelf?
6
A tank is used to store water. If water is used at a rate of 100 litres/day the tank will be empty in
40 days. How long will the water last if it is used at a rate of:
a 50 litres/day
b 250 litres/day
c 350 litres/day?
Cambridge IGCSE Maths Teacher’s Pack, © HarperCollinsPublishers Ltd 2011