Problems on H.C.F and L.C.M
Find the greatest number of four digits which when divided by 10, 15, 21 and 28 leaves 4, 9, 15 and 22 as remainders respectively?
The Largest number of four digits is 9999. Required number must be divisible by L.C.M. of 12,15,18,27 i.e. 540. On dividing 9999 by 540,we get 279 as remainder . Required number = (9999-279) = 9720.
Since the numbers are co-prime, they contain only 1 as the common factor.Also, the given two products have the middle number in common.So, middle number = H.C.F. of 551 and 1073 = 29;First number = 551/29 = 19; Third number = 1073/29 = 37.Required sum = (19 + 29 + 37) = 85.
EXAMIANS