Subtract 27/21 from 12/15
1st number: 12/15, 2nd number: 1 6/21
12/15 - 27/21 is -17/35.
Steps for subtracting fractions
- 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,
27/21 = 27 × 5/21 × 5 = 135/105 - Subtract the two like fractions:
84/105 - 135/105 = 84 - 135/105 = -51/105 - After reducing the fraction, the answer is -17/35
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