Subtract 20/21 from 90/28
1st number: 3 6/28, 2nd number: 20/21
90/28 - 20/21 is 95/42.
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,
90/28 = 90 × 3/28 × 3 = 270/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Subtract the two like fractions:
270/84 - 80/84 = 270 - 80/84 = 190/84 - After reducing the fraction, the answer is 95/42
- In mixed form: 211/42
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