Q:

Can you make 100 using four nines?

A:

Quick Answer

A person can make 100 using the digit 9 four times in an equation. The equation for this math problem is: 99 + (9 / 9) = 100. This solution works because 9 divided by 9 equals 1, and 99 plus 1 equals 100.

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Can you make 100 using four nines?
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Full Answer

Solving this math problem requires one to notice that the number 99, which contains the digit 9 repeated twice, is very close to 100. In fact, 100 - 99 = 1. The other two 9 digits must therefore equal one, and this requires a fraction. The fraction 9 over 9 equals 1. Combining these two facts in a single equation solves this math problem, with the answer being 99 + (9 / 9) = 100.

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