Subtract 30/20 from 18/28
1st number: 18/28, 2nd number: 1 10/20
18/28 - 30/20 is -6/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 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 20 × 7 = 140,
30/20 = 30 × 7/20 × 7 = 210/140 - Subtract the two like fractions:
90/140 - 210/140 = 90 - 210/140 = -120/140 - After reducing the fraction, the answer is -6/7
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