Subtract 90/7 from 21/28
1st number: 21/28, 2nd number: 12 6/7
21/28 - 90/7 is -339/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 7 is 28
Next, find the equivalent fraction of both fractional numbers with denominator 28 - For the 1st fraction, since 28 × 1 = 28,
21/28 = 21 × 1/28 × 1 = 21/28 - Likewise, for the 2nd fraction, since 7 × 4 = 28,
90/7 = 90 × 4/7 × 4 = 360/28 - Subtract the two like fractions:
21/28 - 360/28 = 21 - 360/28 = -339/28
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