Question

Mr Dunn drives 640 m from work at a speed of 4.8m/s mrs. dunn  drives 810 m from work at speed of 5.4m/s they both leave work at the same time how many minutes later is it before the second person gets home

Answer 1

speed = distance/time
time taken = distance/speed

Mr Dunn’s speed = 4.8 m/s
The distance Mr Dunn needs to travel = 810 m
Time taken = 640/4.8 = 133.33 s
133.33 s = 2.22 min

Mrs Dunn’s speed = 5.4 m/s
The distance Mrs Dunn needs to travel = 810 m
Time taken = 810/5.4 = 150 s
150 s = 2.5 min

Time difference = 2.5 - 2.22 = 0.28 min

Answer: It is 0.28 min later before the second person gets home.