Three numbers are in the ratio of 3 : 4 : 5 and their L.C.M. is 2400. Their H.C.F. is
40
Let the numbers be 3x, 4x and 5x. Then, their L.C.M. = 60x. So, 60x = 2400 or x = 40.
∴The numbers are (3 x 40), (4 x 40) and (5 x 40). Hence, required H.C.F. = 40.