Subtract 16/45 from 21/84, Solve 21/84

Subtract 16/45 from 21/84

21/84 - 16/45 is -19/180.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260
Likewise, for the 2nd fraction, since 45 × 28 = 1260,
16/45 = 16 × 28/45 × 28 = 448/1260
Subtract the two like fractions:
315/1260 - 448/1260 = 315 - 448/1260 = -133/1260
After reducing the fraction, the answer is -19/180

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