Subtract 8/18 from 21/72
21/72 - 8/18 is -11/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 18 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 18 × 4 = 72,
8/18 = 8 × 4/18 × 4 = 32/72 - Subtract the two like fractions:
21/72 - 32/72 = 21 - 32/72 = -11/72
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