Subtract 15/8 from 21/18
1st number: 1 3/18, 2nd number: 1 7/8
21/18 - 15/8 is -17/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
15/8 = 15 × 9/8 × 9 = 135/72 - Subtract the two like fractions:
84/72 - 135/72 = 84 - 135/72 = -51/72 - After reducing the fraction, the answer is -17/24
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