This is a great logic puzzle and brain teaser for those who enjoy solving math and critical thinking problems. Let’s see how you solve it! The solution is also provided.

## Challenge:

How many digits are used to write the number \(20^{10}\)?

**A-** 10

**B-** 11

**C-** 12

**D-** 13

**E-** 14

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The correct answer is E.

\(20^{10} = (2 × 10)^{10} = 2^{10 }× 10^{10 }= 1024 × 10^{10}\)

1024 has four digits and \(10^{10 }\) has 11 digits. Why?

Therefore, \(20^{10 }\) has 15 digits.