Subtract 81/4 from 7/21
1st number: 7/21, 2nd number: 20 1/4
7/21 - 81/4 is -239/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
7/21 = 7 × 4/21 × 4 = 28/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
81/4 = 81 × 21/4 × 21 = 1701/84 - Subtract the two like fractions:
28/84 - 1701/84 = 28 - 1701/84 = -1673/84 - After reducing the fraction, the answer is -239/12
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