a car travelled 25km at an average speed of xkm\h.if its speed was increased by 5km\h it covers the distance 15minutes earlier what is the original speed of car?
At least he/she was honest about his/her inability to solve this problem!!
With average speed being x, time taken to travel 25 km =
Increasing speed by 5 km/h means that its speed becomes: x + 5
Time taken to cover distance at new speed of x + 5:
We then get: , which becomes:
25(4)(x + 5) = 25(4x) + x(x + 5) -------- Multiplying by LCD, 4x(x + 5)
(x - 20)(x + 25) = 0
x, or original speed = km/h OR x = - 25 (ignore)