Subtract 90/28 from 7/21
1st number: 7/21, 2nd number: 3 6/28
7/21 - 90/28 is -121/42.
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,
7/21 = 7 × 4/21 × 4 = 28/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84 - Subtract the two like fractions:
28/84 - 270/84 = 28 - 270/84 = -242/84 - After reducing the fraction, the answer is -121/42
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