Greatest Common Divisor

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Find the *Greatest Common Divisor* (GCD) of the numbers 28 and 54.

**Answer**

$28=({2}^{2})(7)$

$54=(2)({3}^{3})$

The GCD of 28 and 54 is the product of the least powers of each prime factor in both.

Thus the GCD of 28 and 54

$=(2)$

$=2$