Question

Three friends namely F, G and H are rowing their boats in a same river. Speeds of F and G in still water are 6 km/h more and 4 km/h more, respectively than speed of H in still water. Ratio of speed of G in downstream to speed of H in downstream is 4 : 3. Find the distance covered by H in 5 hours while going against the stream. Which of the following option alone is not sufficient to find the answer? I The river is flowing at a rate of 2 km/h. II Difference between upstream speed of F and H is 6 km/h. III Ratio of upstream speed G and H is 3 : 2, respectively. IV H covers 240 km downstream in 20 hours.

Q: Answer-Three friends namely F, G and H are rowing their boats in a same river. Speeds of F and G in still...

Let the Speed in still water, of Boat H x kmh, Then Boat F x 6 kmh, Boat G x 4 kmh Let the Speed of stream y kmh x 4 yx y 43 3x 12 3y 4x 4y x y 12 Downstream speed of Boat H Therefore in Upstream, Distance covered by Boat H d 5x y From I, y 2 kmh, x 12 2 10 kmh, d 5 10 2 40 kmh From II, x 6 y x y 6 From III,x 4 yx y 32 2x y 8 3x y x y 8 D 5 8 40 kmh From IV, x y 24020 12 Hence, Either II alone or IV alone is not sufficient to answer the data