Eric Nicholas K's answer to Iniqsha's Primary 6 Maths Speed Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
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The lorry and the truck travel between the same two towns, so the distance travelled by the lorry must be the same as the distance travelled by the truck.

The formula for speed is distance divided by time, or more accurately, average speed is total distance divided by total time.

In other words, total distance travelled is average speed times total time taken.

Since the truck travels at an average speed of 50 km/h over 6 hours, the total distance travelled by the truck is 50 x 6 = 300 km.

This must be the distance (at least the approximate distance) between the two towns.

Since the lorry travels a total of 300 km over a period of 5 hours, the lorry's average speed is 300 / 5 = 60 km/h.