Subtract 21/90 from 12/9
1st number: 1 3/9, 2nd number: 21/90
12/9 - 21/90 is 11/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 9 × 10 = 90,
12/9 = 12 × 10/9 × 10 = 120/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
120/90 - 21/90 = 120 - 21/90 = 99/90 - After reducing the fraction, the answer is 11/10
- In mixed form: 11/10
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