Subtract 7/4 from 81/21
1st number: 3 18/21, 2nd number: 1 3/4
81/21 - 7/4 is 59/28.
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,
81/21 = 81 × 4/21 × 4 = 324/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
7/4 = 7 × 21/4 × 21 = 147/84 - Subtract the two like fractions:
324/84 - 147/84 = 324 - 147/84 = 177/84 - After reducing the fraction, the answer is 59/28
- In mixed form: 23/28
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