Two buses A and B leave the same bus depot, A towards the North and B towads the East. The bus A travels at a speed of 5 km/hr more than that of the bus B. If after four hours the distance between the two buses is 100 km, find the speed of the bus A.	Pick one:
A) 60 kmph B) 40 kmph C) 20 kmph D) 15 kmph E) 25 kmph
Let the speed of the bus B be x km/hr. Then the speed of the bus A will be ( x +5) kmph   Distance traveled in 4 hours is 4x and 4(x + 5) for the two buses respectively   (4x)2 + {4 (x + 5) }2 = (100)2   16x2 + 16x2 + 160x + 400 = 1000   32x2 +160x –9600 = 0   x2 + 5x –300 = 0 (x-15) (x +20 ) = 0   x = 15   :. Speed of the bus A = 15 +5= 
<gadget id="calculator">15 +5</gadget>
<output>20</output>
20 kmph   ANSWER:20 kmph
<result>C</result>
Two buses A and B leave the same bus depot, A towards the North and B towads the East. The bus A travels at a speed of 5 km/hr more than that of the bus B. If after four hours the distance between the two buses is 100 km, find the speed of the bus A.