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3 votes
Grandfath

3. My sister is 12 years older than lam Our combined age is half the age of our
grandfather. Our grandfather is 68 years old. How old am​

User Delforge
by
4.8k points

1 Answer

2 votes

Answer:

11

Explanation:

First, write an equation to represent the situation.

34 = 2a + 12

This equation works because your combined age is half of 68, so 34. If your age is a, then yours sister's age is a + 12. if you add your age to your sister's, you get 2a + 12.

Now just solve for a.

34 = 2a + 12

First, subtract 12 from both sides.

22 = 2a

Then divide both sides by 2.

11 = a

So you are 11 years old. If you need to check your work, your age (11) plus your sister's age (11 + 12, which is 23) is 34, which is half of your grandfather's age.

User Phoku
by
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