Subtract 9/28 from 21/15, Solve 1 6/15

Subtract 9/28 from 21/15

1^st number: 1 6/15, 2^nd number: 9/28

21/15 - 9/28 is 151/140.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 28 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420
Likewise, for the 2nd fraction, since 28 × 15 = 420,
9/28 = 9 × 15/28 × 15 = 135/420
Subtract the two like fractions:
588/420 - 135/420 = 588 - 135/420 = 453/420
After reducing the fraction, the answer is 151/140
In mixed form: 111/140

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