Subtract 21/5 from 18/28
1st number: 18/28, 2nd number: 4 1/5
18/28 - 21/5 is -249/70.
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,
18/28 = 18 × 5/28 × 5 = 90/140 - Likewise, for the 2nd fraction, since 5 × 28 = 140,
21/5 = 21 × 28/5 × 28 = 588/140 - Subtract the two like fractions:
90/140 - 588/140 = 90 - 588/140 = -498/140 - After reducing the fraction, the answer is -249/70
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