Subtract 21/28 from 90/42
1st number: 2 6/42, 2nd number: 21/28
90/42 - 21/28 is 39/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
90/42 = 90 × 2/42 × 2 = 180/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Subtract the two like fractions:
180/84 - 63/84 = 180 - 63/84 = 117/84 - After reducing the fraction, the answer is 39/28
- In mixed form: 111/28
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