Subtract 9/21 from 72/28, Solve 2 16/28

Subtract 9/21 from 72/28

1^st number: 2 16/28, 2^nd number: 9/21

72/28 - 9/21 is 15/7.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
72/28 = 72 × 3/28 × 3 = 216/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
9/21 = 9 × 4/21 × 4 = 36/84
Subtract the two like fractions:
216/84 - 36/84 = 216 - 36/84 = 180/84
After reducing the fraction, the answer is 15/7
In mixed form: 21/7

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