Subtract 90/70 from 21/20
1st number: 1 1/20, 2nd number: 1 20/70
21/20 - 90/70 is -33/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 70 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 70 × 2 = 140,
90/70 = 90 × 2/70 × 2 = 180/140 - Subtract the two like fractions:
147/140 - 180/140 = 147 - 180/140 = -33/140
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