Subtract 81/28 from 75/21
1st number: 3 12/21, 2nd number: 2 25/28
75/21 - 81/28 is 19/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
75/21 = 75 × 4/21 × 4 = 300/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
81/28 = 81 × 3/28 × 3 = 243/84 - Subtract the two like fractions:
300/84 - 243/84 = 300 - 243/84 = 57/84 - After reducing the fraction, the answer is 19/28
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