Subtract 10/21 from 7/15
7/15 - 10/21 is -1/105.
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,
7/15 = 7 × 7/15 × 7 = 49/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
10/21 = 10 × 5/21 × 5 = 50/105 - Subtract the two like fractions:
49/105 - 50/105 = 49 - 50/105 = -1/105
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