calculate how much time could be saved if the train would run at its usual speed , given that it ran at 2 / 3 of its own speed and got to its destination in 20 hours ?
"new speed = 2 / 3 of usual speed new time = 2 / 3 of usual time 2 / 3 of usual time = 20 hrs usual time = 20 * 2 / 3 = 13.33 hrs time saved = 22 - 13.33 = 8.67 hrs answer is d"
add(divide(reminder(subtract(multiply(20, const_60), multiply(multiply(20, divide(2, 3)), const_60)), const_60), const_100), floor(divide(subtract(multiply(20, const_60), multiply(multiply(20, divide(2, 3)), const_60)), const_60)))