Subtract 21/20 from 15/70
1st number: 15/70, 2nd number: 1 1/20
15/70 - 21/20 is -117/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
15/70 = 15 × 2/70 × 2 = 30/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Subtract the two like fractions:
30/140 - 147/140 = 30 - 147/140 = -117/140
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