Respuesta :

mj3mar

Answer:

John is 17,

Susan is 14,

and Khalid is 9.

Step-by-step explanation:

a = John's age

b = Susan's age

c = Khalid's age

Let's set our rules from the given information.

a = b + 3

c = b - 5

a + b + c = 40

Now, we can solve for b through substitution.

(b + 3) + b + (b - 5) = 40

3b - 2 = 40

3b = 42

b = 14

So, now that we have Susan's age, we can follow the rules and see if it holds.

17 + 14 + 9 = 40 Viola!