Subtract 15/21 from 1/15
1/15 - 15/21 is -68/105.
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,
1/15 = 1 × 7/15 × 7 = 7/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
15/21 = 15 × 5/21 × 5 = 75/105 - Subtract the two like fractions:
7/105 - 75/105 = 7 - 75/105 = -68/105
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