Subtract 9/4 from 21/72
1st number: 21/72, 2nd number: 2 1/4
21/72 - 9/4 is -47/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 4 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 4 × 18 = 72,
9/4 = 9 × 18/4 × 18 = 162/72 - Subtract the two like fractions:
21/72 - 162/72 = 21 - 162/72 = -141/72 - After reducing the fraction, the answer is -47/24
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