Subtract 15/8 from 7/21
1st number: 7/21, 2nd number: 1 7/8
7/21 - 15/8 is -37/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
7/21 = 7 × 8/21 × 8 = 56/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168 - Subtract the two like fractions:
56/168 - 315/168 = 56 - 315/168 = -259/168 - After reducing the fraction, the answer is -37/24
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