Question

Cameron's uncle is 3 times old as he is. 4 years ago, he was 4 times older. How old is Cameron?

Answer 1

Let Cameron's age be c, and Cameron's uncle's age be u.

Cameron's uncle is 3 times as old as he is: u = 3c.

Four years ago, his uncle was 4 times older: u - 4 = 4(c - 4).

Now solve this system:

u = 3c

u - 4 = 4(c - 4)

Substitute 3c for u into the second equation and solve for c.

u - 4 = 4(c - 4)

3c - 4 = 4(c - 4)

3c - 4 = 4c - 16

-c - 4 = -16

-c = -12

c = 12

Answer:

Cameron is 12.

Answer 2

Let Cameron be x years old now.

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Now:

Cameron = x

Uncle =3x

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4 years ago:

Cameron = x - 4

Uncle = 3x - 4

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4 years ago, Uncle is 4 times older:

3x - 4 = 4(x - 4)

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Find x:

3x - 4 = 4(x - 4)

3x - 4 = 4x - 16

4x - 3x = 16 - 4

x = 12

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Find the age:

Cameron = x = 12

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Answer: Cameron is 12 years old now.