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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?

View solutions

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 6 million people

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

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

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That seems reasonable. Find out if you're right!

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by Ron Lauterbach

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