Subtract 90/20 from 21/40
1st number: 21/40, 2nd number: 4 10/20
21/40 - 90/20 is -159/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
90/20 = 90 × 2/20 × 2 = 180/40 - Subtract the two like fractions:
21/40 - 180/40 = 21 - 180/40 = -159/40
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