a 600 meter long train crosses a signal post in 15 seconds . how long will it take to cross a 3 kilometer long bridge , at the same speed ?
"s = 600 / 15 = 40 mps s = 3600 / 40 = 90 sec = 1.5 min answer : e"
divide(divide(multiply(3, const_1000), speed(600, 15)), const_60)