Subtract 7/8 from 21/36
21/36 - 7/8 is -7/24.
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,
7/8 = 7 × 9/8 × 9 = 63/72 - Subtract the two like fractions:
42/72 - 63/72 = 42 - 63/72 = -21/72 - After reducing the fraction, the answer is -7/24
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