Subtract 21/5 from 90/28
1st number: 3 6/28, 2nd number: 4 1/5
90/28 - 21/5 is -69/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 5 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
90/28 = 90 × 5/28 × 5 = 450/140 - Likewise, for the 2nd fraction, since 5 × 28 = 140,
21/5 = 21 × 28/5 × 28 = 588/140 - Subtract the two like fractions:
450/140 - 588/140 = 450 - 588/140 = -138/140 - After reducing the fraction, the answer is -69/70
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