Subtract 72/21 from 81/4
1st number: 20 1/4, 2nd number: 3 9/21
81/4 - 72/21 is 471/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
81/4 = 81 × 21/4 × 21 = 1701/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
72/21 = 72 × 4/21 × 4 = 288/84 - Subtract the two like fractions:
1701/84 - 288/84 = 1701 - 288/84 = 1413/84 - After reducing the fraction, the answer is 471/28
- In mixed form: 1623/28
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