Subtract 12/15 from 6/21
6/21 - 12/15 is -18/35.
Steps for subtracting fractions
- 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,
6/21 = 6 × 5/21 × 5 = 30/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
12/15 = 12 × 7/15 × 7 = 84/105 - Subtract the two like fractions:
30/105 - 84/105 = 30 - 84/105 = -54/105 - After reducing the fraction, the answer is -18/35
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