Subtract 80/70 from 21/28
1st number: 21/28, 2nd number: 1 10/70
21/28 - 80/70 is -11/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
80/70 = 80 × 2/70 × 2 = 160/140 - Subtract the two like fractions:
105/140 - 160/140 = 105 - 160/140 = -55/140 - After reducing the fraction, the answer is -11/28
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