Subtract 30/28 from 21/20
1st number: 1 1/20, 2nd number: 1 2/28
21/20 - 30/28 is -3/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
30/28 = 30 × 5/28 × 5 = 150/140 - Subtract the two like fractions:
147/140 - 150/140 = 147 - 150/140 = -3/140
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