Subtract 21/9 from 20/10
1st number: 2 0/10, 2nd number: 2 3/9
20/10 - 21/9 is -1/3.
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,
20/10 = 20 × 9/10 × 9 = 180/90 - Likewise, for the 2nd fraction, since 9 × 10 = 90,
21/9 = 21 × 10/9 × 10 = 210/90 - Subtract the two like fractions:
180/90 - 210/90 = 180 - 210/90 = -30/90 - After reducing the fraction, the answer is -1/3
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