Subtract 6/84 from 21/27, Solve 21/27

Subtract 6/84 from 21/27

21/27 - 6/84 is 89/126.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 84 is 756

Next, find the equivalent fraction of both fractional numbers with denominator 756
For the 1st fraction, since 27 × 28 = 756,
21/27 = 21 × 28/27 × 28 = 588/756
Likewise, for the 2nd fraction, since 84 × 9 = 756,
6/84 = 6 × 9/84 × 9 = 54/756
Subtract the two like fractions:
588/756 - 54/756 = 588 - 54/756 = 534/756
After reducing the fraction, the answer is 89/126

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