Try using critical thinking challenges to help you or your student improve strategic thinking and logic skills.

## Challenge:

In 2013, the product of the ages (in integers) of a father and his son is 2013. What is the difference of their ages in 2015?

**A-** 20

**B-** 24

**C-** 28

**D-** 30

**E-** 32

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The correct answer is C.

Find the factors of 2013:

1, 3, 11, 33, 61, 671, 2013

From all the factors of 2013, only 33 and 61 could be the ages of a father and his son. (The product of two ages should be 2013)

The difference of 61 and 33 is 28 years and this number won’t change in 2015!