Subtract 21/18 from 9/8
1st number: 1 1/8, 2nd number: 1 3/18
9/8 - 21/18 is -1/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
9/8 = 9 × 9/8 × 9 = 81/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Subtract the two like fractions:
81/72 - 84/72 = 81 - 84/72 = -3/72 - After reducing the fraction, the answer is -1/24
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