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44 votes
Mike's age is 3 times John's age. In 12 years, Mike will be twice as old as John. How old are Mike and John now?

Please give me step by step explanation! :)

User Rolf Huisman
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1 Answer

8 votes
8 votes

Answers:

John = 12 years old

Mike = 36 years old

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Step-by-step explanation:

j = John's current age

3j = Mike's current age, since he's three times as old as John.

Now fast forward the clock 12 years to get these future ages

j+12 = John's future age

3j+12 = Mike's future age

We're told that at this point in the future, Mike will be twice as old as John, so,

Mike's future age = 2*(John's future age)

3j+12 = 2*(j+12)

3j+12 = 2j+24

3j-2j = 24-12

j = 12

Therefore, John is currently 12 years old.

This makes Mike to be 3j = 3*12 = 36 years old currently.

Twelve years into the future John and Mike will be 12+12 = 24 and 36+12 = 48 respectively. Notice that 24*2 = 48 to help confirm the answers.

User Elementsense
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