Subtract 8/9 from 21/72
21/72 - 8/9 is -43/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
8/9 = 8 × 8/9 × 8 = 64/72 - Subtract the two like fractions:
21/72 - 64/72 = 21 - 64/72 = -43/72
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