Subtract 30/9 from 72/28, Solve 2 16/28

Subtract 30/9 from 72/28

1^st number: 2 16/28, 2^nd number: 3 3/9

72/28 - 30/9 is -16/21.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 9 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 28 × 9 = 252,
72/28 = 72 × 9/28 × 9 = 648/252
Likewise, for the 2nd fraction, since 9 × 28 = 252,
30/9 = 30 × 28/9 × 28 = 840/252
Subtract the two like fractions:
648/252 - 840/252 = 648 - 840/252 = -192/252
After reducing the fraction, the answer is -16/21

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