Subtract 45/21 from 12/15, Solve 12/15

Subtract 45/21 from 12/15

1^st number: 12/15, 2^nd number: 2 3/21

12/15 - 45/21 is -47/35.

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

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
12/15 = 12 × 7/15 × 7 = 84/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
45/21 = 45 × 5/21 × 5 = 225/105
Subtract the two like fractions:
84/105 - 225/105 = 84 - 225/105 = -141/105
After reducing the fraction, the answer is -47/35

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