Subtract 28/20 from 21/35
1st number: 21/35, 2nd number: 1 8/20
21/35 - 28/20 is -4/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 35 × 4 = 140,
21/35 = 21 × 4/35 × 4 = 84/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
28/20 = 28 × 7/20 × 7 = 196/140 - Subtract the two like fractions:
84/140 - 196/140 = 84 - 196/140 = -112/140 - After reducing the fraction, the answer is -4/5
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