Question

Two cars start from the same place at the same time but in opposite directions. Their speed are 80km/h and 65km/h.after how long will they take to be 580 km apart

Answer 1

To be 580 km apart we can take the time taken by each of them to travel their part of the distance.

A____xkm______start___________ykm__________B.

we can do a hit-and-trial method here as shown:

1st hour: distance = 65*1 + 80*1 =145 km

2nd hour: distance = 65*2 + 80*2= 130+160=290 km

3rd hour: distance = 65*3 + 80*3= 195+240=435 km

4th hour: distance = 65*4 + 80*4= 260+320=580km

Therefore they take 4 hours to be 580 km apart.