Answer:
Rate of the faster bus: 121 km/hr
Rate of the slower bus:129 km/hr
Explanation:
Let the speed of slower one is x km/hr
If the the speed faster is 8 km/hr more than slower then
speed of faster one is (x+7)km /hr
It is given that both bus traveled for time 4 hours.
we will use formula for distance = speed*time
for slower bus
speed : x km/hr
time = 7 hour
distance = x km/hr * 7 hour = 7x km
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for Faster bus
speed : (x+8) km/hr
time = 7 hour
distance = (x+8) km/hr * 7 hour = (7x + 56 )km
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Total distance covered by both of bus in 7 hours = (7x + 56 )km+ 7x km
= (14x+56)km ____________1
But, it is given both bus were 1750 km apart and they meet which means that together they covered 1750 km.
Thus, value of equation 1 should be equal to 1750 km as shown below
(14x+56)km = 1750 km
=> 14x = 1750 - 56
=> 14x = 1694
=>x = 1694/14 = 121.
Thus,
speed of slower bus = 121km/hr
speed of faster bus = (x+8)km/hr = (121+8) km/hr = 129 km/hr