My son is seven times older than my grandson and i am 12 times older than my grandson. if you add all our ages together, the sum is 100 years. can you tell me my age in years?

Given:
I: My age.
S: My son.
G: My grandson.
If you add all our ages together, the sum is 100 years.
SOLVING:

I + S + G = 100 ===> First equation.
S = 7G ===> Second equation.
I = 12G ===> Third equation.

We replace the second equation and the third ecuation in the first equation:
12G + 7G + G = 100
20G = 100
G =
G = 5 years old. ===> My grandson.
S = 7(5)
S = 35 years old. ===> My son.
I = 12(5)
I = 60 years old. ===> My age. SOLUTION

TESTING:


GOOD LUCK...!!!