Subtract 21/9 from 15/8
1st number: 1 7/8, 2nd number: 2 3/9
15/8 - 21/9 is -11/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
15/8 = 15 × 9/8 × 9 = 135/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72 - Subtract the two like fractions:
135/72 - 168/72 = 135 - 168/72 = -33/72 - After reducing the fraction, the answer is -11/24
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