machines x and y produce bottles at their respective constant rates . machine x produces k bottles in 3 hours and machine y produces k bottles in 2 hours . how many hours does it take machines x and y , working simultaneously , to produce 12 k bottles ?
x rate = k / 3 y rate = k / 2 k / 3 + k / 2 = 12 k / t solving t = 72 / 5 answer d
divide(multiply(12, divide(add(3, 2), 2)), 2)