SOLUTION: Tom is 4 times as old as Todd. In 3 years Tom's age will be 13 years more than 2 times as old as Todd. How old is Tom?

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Question 102516: Tom is 4 times as old as Todd. In 3 years Tom's age will be 13 years more than 2 times as old as Todd. How old is Tom?
Answer by mjgulinello(10) About Me  (Show Source):
You can put this solution on YOUR website!
Let m = Tom's age
Let d = Todd's age
Now we have to write equations that compare their ages.
We know tom is 4 times as old as Todd, so
m+=+4d
We also know in 3 years Tom's age will be 13 years more than 2 times as old as Todd, so
m+%2B+3+=+2%28d%2B3%29+%2B+13
Now we can plug the first equation into the second to get:
4d+%2B+3+=+2%28d%2B3%29+%2B+13
Use the distributive property on the right side of the equation.
4d+%2B+3+=+2d%2B6+%2B+13
Combine like terms
4d+%2B+3+=++2d+%2B+19
Subtract 2d from each side
2d+%2B+3+=+19
Subtract 3 from each side
2d+=+16
Divide each side by 2
d+=+8
So we now know Todd is 8. We can plug that in to find Tom's age.
m+=+4+%2A+8
m+=+32
Tom is 32.
We can check this by using the second equation.
m+%2B+3+=+2%28d%2B3%29+%2B+13
32+%2B+3+=+2%288%2B3%29+%2B+13
35+=+2+%2A+11+%2B+13
35+=+22+%2B+13
35+=+35
Check.
That's all for this problem.
-Mike