A train P running at the speed of 80km/h crosses another train Q running at 70 km/h in opposite direction in 18 seconds. If the length of Q is 150% that of P, then what is the length of P?
Answer & explanation
Correct answer: option 1
Relative speed = 80 + 70 = 150 km/h = 150 × \(\frac{5}{18}\) m/sec
Total distance covered = 150 × \(\frac{5}{18}\) × 18 = 750 m
Length of trains:
P : Q = 2 : 3 (150% = \(\frac{150}{100}\) = \(\frac{3}{2}\) )
Total distance = 5R
5R = 750
1R = 150
⇒ Length of P = 2R = 300 m