Subtract 21/15 from 3/12
1st number: 3/12, 2nd number: 1 6/15
3/12 - 21/15 is -23/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
3/12 = 3 × 5/12 × 5 = 15/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Subtract the two like fractions:
15/60 - 84/60 = 15 - 84/60 = -69/60 - After reducing the fraction, the answer is -23/20
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