A boat can go 5 km upstream and 71/2 km downstream in 45 minutes. If…

Question

A boat can go 5 km upstream and 71/2 km downstream in 45 minutes. If can also go 5 km downstream and 2.5 km upstream in 25 minutes. How much time (in minutes) will it take to go 6 km upstream?

Accepted Answer

Option B. 36. Answer & Solution Answer: Option B Solution: & 5x - y + 152 ( x + y ) = 3/4 hr . . . . ( i ) & 2.5 × 2x - y + 5 × 2x + y = 5 × 212 hr . . . . ( ii ) & 52 ( x + y ) = 112 & x + y = 30 & Put x + y = 30 in equation ( i ) & 5x - y + 152 × 30 = 3/4 & 5x - y = 1/2 & x - y = 10 & Now,…