Subtract 16/9 from 21/84, Solve 21/84

Subtract 16/9 from 21/84

1^st number: 21/84, 2^nd number: 1 7/9

21/84 - 16/9 is -55/36.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 9 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252
Likewise, for the 2nd fraction, since 9 × 28 = 252,
16/9 = 16 × 28/9 × 28 = 448/252
Subtract the two like fractions:
63/252 - 448/252 = 63 - 448/252 = -385/252
After reducing the fraction, the answer is -55/36

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