Subtract 21/15 from 12/14, Solve 12/14

Subtract 21/15 from 12/14

1^st number: 12/14, 2^nd number: 1 6/15

12/14 - 21/15 is -19/35.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 15 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 14 × 15 = 210,
12/14 = 12 × 15/14 × 15 = 180/210
Likewise, for the 2nd fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210
Subtract the two like fractions:
180/210 - 294/210 = 180 - 294/210 = -114/210
After reducing the fraction, the answer is -19/35

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