Question

Three friends all have ages that are consecutive internet’s. The sum of their ages is 57. What is the age of the oldest friend

Answer 1

To solve this problem you must apply the proccedure shown below:

1. You have that the ages of three friends are consecutive integers and the sum of their ages is $57$. Therefore, let's call the age of the youngest friend $x$, the middle age $(x+1)$ and the age of the oldest $(x+2)$. Then, you can write the following expression and solve for $x$:

$x+(x+1)+(x+2)=57\\ 3x+3=57\\ x=18$

2. Therefore, the age of the oldest friend is:

$x+2=18+2=20$

The answer is: $20$ years old.