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Twice As Old in 20 Years

Algebra Level 1

A father explains:

I am four times as old as my son. In 20 years I will be twice as old as my son.

How old is this father currently?

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, interactive explorations.

Used and loved by over 7 million people

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including olympiad champions, researchers, and professionals.

Your answer seems reasonable. Find out if you're right!

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by Ron Lauterbach

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