Subtract 21/20 from 40/90
1st number: 40/90, 2nd number: 1 1/20
40/90 - 21/20 is -109/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
40/90 = 40 × 2/90 × 2 = 80/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Subtract the two like fractions:
80/180 - 189/180 = 80 - 189/180 = -109/180
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