Subtract 9/8 from 21/36
1st number: 21/36, 2nd number: 1 1/8
21/36 - 9/8 is -13/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 36 × 2 = 72,
21/36 = 21 × 2/36 × 2 = 42/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
9/8 = 9 × 9/8 × 9 = 81/72 - Subtract the two like fractions:
42/72 - 81/72 = 42 - 81/72 = -39/72 - After reducing the fraction, the answer is -13/24
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