A bus can cover x km distance with speed of p km/hr in four hours. The speed…

2024

A bus can cover x km distance with speed of p km/hr in four hours. The speed of stream is q km/hr and a boat covers x km distance in downstream & upstream with speed of p km/hr in total 9 hours. If boat takes 1 hour more to cover 30 km upstream that 20 km downstream, find the value of ‘x’?

  1. A.

    3p + 2q

  2. B.

    60 + 2q + 30

  3. C.

    5q + p

  4. D.

    (1.5p + 4q) + 35

  5. E.

    4q + 2p

Attempted by 3 students.

Show answer & explanation

Correct answer: D

The bus condition gives x = 4p.

For the boat, x/(p+q) + x/(p-q) = 9. Substituting x = 4p gives q = p/3.

Also, 30/(p-q) is one hour more than 20/(p+q). Using q = p/3 gives p = 30 and q = 10, so x = 120. Among the options, (1.5p + 4q) + 35 = 45 + 40 + 35 = 120.

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