Subtract 15/7 from 21/15
1st number: 1 6/15, 2nd number: 2 1/7
21/15 - 15/7 is -26/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
21/15 = 21 × 7/15 × 7 = 147/105 - Likewise, for the 2nd fraction, since 7 × 15 = 105,
15/7 = 15 × 15/7 × 15 = 225/105 - Subtract the two like fractions:
147/105 - 225/105 = 147 - 225/105 = -78/105 - After reducing the fraction, the answer is -26/35
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