Subtract 21/32 from 21/72
21/72 - 21/32 is -35/96.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 32 is 288
Next, find the equivalent fraction of both fractional numbers with denominator 288 - For the 1st fraction, since 72 × 4 = 288,
21/72 = 21 × 4/72 × 4 = 84/288 - Likewise, for the 2nd fraction, since 32 × 9 = 288,
21/32 = 21 × 9/32 × 9 = 189/288 - Subtract the two like fractions:
84/288 - 189/288 = 84 - 189/288 = -105/288 - After reducing the fraction, the answer is -35/96
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