Subtract 21/9 from 12/10
1st number: 1 2/10, 2nd number: 2 3/9
12/10 - 21/9 is -17/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 9 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 10 × 9 = 90,
12/10 = 12 × 9/10 × 9 = 108/90 - Likewise, for the 2nd fraction, since 9 × 10 = 90,
21/9 = 21 × 10/9 × 10 = 210/90 - Subtract the two like fractions:
108/90 - 210/90 = 108 - 210/90 = -102/90 - After reducing the fraction, the answer is -17/15
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