Let us denote Maggie's years with M and her brother's years with Y. We know that Maggie's brother is 5 years younger than three times her age.So, we can write: Y=3*M-5 (1) We also know that the sum of their ages is 51, so we can write: Y+M=51 (2) We can put the first equation (1) in the second (2) and we will obtain: 3M-5+M=51 4M-5=51 4M=51+5 4M=56 M=56/4 M=14 Maggie is 14 years old. And her brother is : Y=51-14=34 years old.
