Subtract 7/21 from 3/15
3/15 - 7/21 is -2/15.
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,
3/15 = 3 × 7/15 × 7 = 21/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105 - Subtract the two like fractions:
21/105 - 35/105 = 21 - 35/105 = -14/105 - After reducing the fraction, the answer is -2/15
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