Subtract 90/21 from 27/28
1st number: 27/28, 2nd number: 4 6/21
27/28 - 90/21 is -93/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
27/28 = 27 × 3/28 × 3 = 81/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Subtract the two like fractions:
81/84 - 360/84 = 81 - 360/84 = -279/84 - After reducing the fraction, the answer is -93/28
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