Two boys A and B start at the same time to ride from Delhi to Meerut, 60 km away. A rides 4 km/h slower than B. B reaches Meerut and at once turns back meeting A at a place 12 km from Meerut. Find the speed of A.
Answer & explanation
Correct answer: option 2
Let speed of B = s km/hr
Speed of A = ( s - 4 ) km/hr
Distance traveled by B = ( 60 + 12 ) km/hr = 72 km/hr
Distance traveled by A = ( 60 - 12 ) km/hr = 48 km/hr
We know that ,
Time = \(\frac{Distance }{Speed}\)
According to question ,
\(\frac{48 }{( s - 4 )}\) = \(\frac{72 }{s }\)
48 s = 72 s - 288
24s = 288
s = 12
Speed of A = ( s - 4 )
= ( 12 - 4 )
= 8 km/hr