Greatest Common Divisor

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Find the *Greatest Common Divisor* (GCD) of the numbers 20 and 200.

**Answer**

$20=({2}^{2})(5)$

$200=({2}^{3})({5}^{2})$

The GCD of 20 and 200 is the product of the least powers of each prime factor in both.

Thus the GCD of 20 and 200

$=({2}^{2})(5)$

$=20$