LCM of 10, 15, 25 = 150When we drive 2641 by 150 the remainder is 91.But the remainder should be 7.So, the number to be subtracted from 2641 is 91 - 7 = 84.
Since the difference between the divisors and the respective remainders is not constant, back substitution is the convenient method. None of the given numbers is satisfying the condition.
EXAMIANS