Subtract 9/15 from 27/21, Solve 1 6/21

Subtract 9/15 from 27/21

1^st number: 1 6/21, 2^nd number: 9/15

27/21 - 9/15 is 24/35.

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,
27/21 = 27 × 5/21 × 5 = 135/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
9/15 = 9 × 7/15 × 7 = 63/105
Subtract the two like fractions:
135/105 - 63/105 = 135 - 63/105 = 72/105
After reducing the fraction, the answer is 24/35

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