the speed at which a girl can row a boat in still water is 75 kmph . if he rows downstream , where the speed of current is 15 kmph , what time will he take to cover 300 metres ?
"speed of the boat downstream = 75 + 15 = 90 kmph = 90 * 5 / 18 = 25 m / s hence time taken to cover 400 m = 400 / 25 = 16 seconds . answer : a"
divide(multiply(300, const_3_6), add(75, 15))