SSC CGL 20201)A group of three friends, K, L and M, are sitting in a cafe. Their average age is 24 years. Another friend ‘N’ joins the group and the new average age of the group becomes 23 years. If another friend ‘R’, whose age is 2 years more than that of ‘N’, replaces ‘K’, then the average age of L. M, N and R becomes 22.5 years. What is the age of K?
24 years
Total age of K, L, and M = 24 x 3 = 72 years ; Total age of K, L, M and N = 23 x 4 = 92 years ; Age of N = 92 - 72 = 20 ears ; Age of R = 20 + 2 = 22 years ; Total age of K, L, M, N and R = 92 + 22 = 114 years ; And, total age of L, M, N and R = 22.5 x 4 = 90 years ; So, Age of K = 114 - 90 = 24 years