Multiple choice

Ratio of speed of boat in downstream and speed of stream is (17 : 2), if speed of stream is (4) km per hr, then find distance travelled by boat (in km) in upstream in (5.5) hours.

  1. 129

  2. 134

  3. 143

  4. 120

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Downstream:stream speed ratio is 17:2. Stream speed = 4 km/hr, so downstream speed = (17/2) × 4 = 34 km/hr. Let boat speed = b, stream speed = s. Downstream = b + s = 34, s = 4, so b = 30 km/hr. Upstream speed = b - s = 30 - 4 = 26 km/hr. Distance in 5.5 hours upstream = 26 × 5.5 = 143 km. Options A, B, D are incorrect.