Subtract 20/90 from 21/10
1st number: 2 1/10, 2nd number: 20/90
21/10 - 20/90 is 169/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 10 × 9 = 90,
21/10 = 21 × 9/10 × 9 = 189/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
20/90 = 20 × 1/90 × 1 = 20/90 - Subtract the two like fractions:
189/90 - 20/90 = 189 - 20/90 = 169/90 - In mixed form: 179/90
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