Subtract 6/84 from 21/45, Solve 21/45

Subtract 6/84 from 21/45

21/45 - 6/84 is 83/210.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 84 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 45 × 28 = 1260,
21/45 = 21 × 28/45 × 28 = 588/1260
Likewise, for the 2nd fraction, since 84 × 15 = 1260,
6/84 = 6 × 15/84 × 15 = 90/1260
Subtract the two like fractions:
588/1260 - 90/1260 = 588 - 90/1260 = 498/1260
After reducing the fraction, the answer is 83/210

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