Subtract 21/10 from 20/90
1st number: 20/90, 2nd number: 2 1/10
20/90 - 21/10 is -169/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 10 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
20/90 = 20 × 1/90 × 1 = 20/90 - Likewise, for the 2nd fraction, since 10 × 9 = 90,
21/10 = 21 × 9/10 × 9 = 189/90 - Subtract the two like fractions:
20/90 - 189/90 = 20 - 189/90 = -169/90
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