Subtract 3/8 from 21/72
21/72 - 3/8 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 8 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 8 × 9 = 72,
3/8 = 3 × 9/8 × 9 = 27/72 - Subtract the two like fractions:
21/72 - 27/72 = 21 - 27/72 = -6/72 - After reducing the fraction, the answer is -1/12
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