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4.2 Solving problems involving average speed

3 How long will it take Seb to run 4000 m at an average speed of 5 m/s?
Give your answer in minutes and seconds.
4 Sundeep travels by train to a meeting in Barcelona.
Barcelona is 270 km from where he lives. He catches the train
at 9:45 a.m. The train travels at an average speed of 120 km/h.
At what time will the train arrive in Barcelona?

5 Steffan cycled 10 km in 45 minutes. He rested for
20 minutes then cycled a further 8 km in 40 minutes. To change a decimal or fraction of an
Work out his average speed for the whole journey. hour into minutes, multiply by 60, for
Give your answer correct to one decimal place. example:
1 of an hour Æ 1 × 60 = 20 minutes
6 Avani runs and walks 10 km from her home to work 3 3
and then back again each day. 0.2 hours Æ 0.2 × 60 = 12 minutes
She runs the first 8 km at a speed of 12 km/h. To change minutes back to hours,

She walks the last 2 km at a speed of 5 km/h. divide by 60, for example:
a Work out the total time it takes her to travel from 72 minutes Æ 72 ÷ 60 = 1.2 hours
home to work each day. Give your answer in 1
hours and minutes. 140 minutes Æ 140 ÷ 60 = 2 3 hours
b Work out her average speed for the whole journey.
Avani works Monday to Friday every week.
c Work out the total time that Avani spends travelling to and from work in one week.

7 Greg lives in the UK. His car shows the speed he Type of road Raining Not raining
is travelling, in miles per hour. Motorway 110 km/h 130 km/h
Greg went on holiday to France. He took his car. Dual carriageway 100 km/h 110 km/h
He saw this table that shows information about Open road 80 km/h 90 km/h
the speed limits on the different types of road in Town 50 km/h 50 km/h
France. The speeds are shown in kilometres per hour.
a Work out the speed limit, in miles per hour, when Greg was travelling on:
i a motorway when it was raining ii an open road when it was not raining
iii a dual carriageway when it was raining iv a town.
b On Tuesday it was not raining. Greg drove on the French motorway at 75 miles per hour.
Was he breaking the speed limit? Explain your answer.
c On Thursday it was raining. Greg drove on an open road in France at 55 miles per hour.
Was he breaking the speed limit? Explain your answer.

8 A high-speed train travels at a maximum speed of 320 kilometres
per hour (km/h).
Work out the maximum speed of this train in metres per second (m/s).
Give your answer to the nearest whole number.

9 An aeroplane travels at a cruising speed of 570 miles per hour.
Work out the cruising speed of this aeroplane in metres per second (m/s).
Give your answer to the nearest whole number.

4 Length, mass, capacity and time 37