Question

3.3 Dr Seroto travelled from his office directly to the school 45 km away. He travelled at an average speed of 100 km per hour and arrived at the school at 11:20. Verify, showing ALL calculations, whether Dr Seroto left his office at exactly 10:50. The following formula may be used: Distance = average speed x time


`distance= average sped * time`
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Answer 1

Answer: We can use the formula Distance = Average speed x time to verify whether Dr Seroto left his office at exactly 10:50.

Let t be the time Dr Seroto left his office. Then, the time he arrived at the school can be expressed as:

t + (Distance/Average speed) = 11:20

We know that the distance is 45 km and the average speed is 100 km/hour. Substituting these values, we get:

t + (45/100) = 11:20

We need to convert the time on the right-hand side to hours. 11:20 can be written as:

11 + 20/60 = 11.33 hours

Substituting this value, we get:

t + 0.45 = 11.33

Solving for t, we get:

t = 11.33 - 0.45

t = 10.88 hours

This is not equal to 10:50, which is 10.83 hours. Therefore, Dr Seroto did not leave his office at exactly 10:50.