<PRE><B>Question 722099</B>
let the speed of bus be x
time taken to reach the city = 264/x

speed increased by 4

speed = x+4

Time taken to reach city now = 264/(x+4)
After increase in speed it takes 1/2 hour less

It reaches same time

264/x - 264/(x+4) = 1/2

multiply by 2x(x+4)

264*2(x+4)-2*264x=x(x+4)

528x+2112-528x=x^2+4x

x^2+4x-2112=0

x^2+4x+4 = 2112+4

(x+2)^2= 2116

take square root

x+2 = +/- 46

x= 44 OR -48

ignore negative

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