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Billy is 4 years older than Johnny. Sally is twice as old as Johnny. If the sum of their ages is 32, how old iseach kid? PLEASE HELP

User TungstenX
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1 Answer

22 votes
22 votes

We can pose this question as follows:

1. We have that Billy is 4 years older than Johnny:

B = J + 4

2. Sally is twice as old as Johnny:

S = 2J

3. The sum of their ages is 32, we have:

B + S + J = 32.

Then, we have that:

J + 4 + 2J + J = 32 (we substitute the previous values of the equations above).

Summing the like terms, we can find the value of J:

4J + 4 = 32 ---> 4J = 32 - 4 ---> J = 28/4 ---> J = 7.

Then, Johnny is 7 years old.

Sally is:

S = 2 * J ---> S = 2 * 7 ---> S = 14 years old.

And Billy is:

B = J + 4 ---> B = 7 + 4 ---> B = 11 years old.

User Lusc
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