walking at 3 / 4 of his usual place , a man reaches his office 20 minute late . find his usual time ?
let the original speed be s and time be t if new speed = s ã — 3 / 4 , then new time would be t ã — 4 / 3 ( d = st = constant ) . given , 3 t / 4 â ˆ ’ t = 20 t / 3 â ‡ ’ t = 60 minutes = 1 hour answer : a
divide(multiply(multiply(divide(multiply(20, 3), 4), 4), const_2), const_60)