A man takes twice as long to row a distance against the stream as to row the same distance in favor of the stream. What is the ratio of the speed of the boat (in still water) and the stream? एक व्यक्ति धारा के प्रतिकूल जाने में ,धारा के अनुकूल जाने की तुलना में दोगुना समय लेता है। नाव की गति और धारा की गति (शान्त जल में ) में अनुपात क्या होगा ?

Let boat speed in still water = b, stream speed = s. Downstream speed = b+s, upstream speed = b-s. Time upstream = 2 × time downstream, so distance/(b-s) = 2 × distance/(b+s). This gives b+s = 2(b-s), so b+s = 2b-2s, meaning 3s = b, or b:s = 3:1. At 3:1 ratio, downstream is 4x, upstream is 2x, giving the required 2:1 time ratio. Option A (2:1) would mean b = 2s, giving speeds 3s and s with time ratio 3:1, not 2:1.