Subtract 8/15 from 7/21
7/21 - 8/15 is -1/5.
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,
7/21 = 7 × 5/21 × 5 = 35/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
8/15 = 8 × 7/15 × 7 = 56/105 - Subtract the two like fractions:
35/105 - 56/105 = 35 - 56/105 = -21/105 - After reducing the fraction, the answer is -1/5
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