Subtract 27/15 from 9/21, Solve 9/21

Subtract 27/15 from 9/21

1^st number: 9/21, 2^nd number: 1 12/15

9/21 - 27/15 is -48/35.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
9/21 = 9 × 5/21 × 5 = 45/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
27/15 = 27 × 7/15 × 7 = 189/105
Subtract the two like fractions:
45/105 - 189/105 = 45 - 189/105 = -144/105
After reducing the fraction, the answer is -48/35

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