Subtract 21/10 from 18/9
1st number: 2 0/9, 2nd number: 2 1/10
18/9 - 21/10 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 10 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 9 × 10 = 90,
18/9 = 18 × 10/9 × 10 = 180/90 - Likewise, for the 2nd fraction, since 10 × 9 = 90,
21/10 = 21 × 9/10 × 9 = 189/90 - Subtract the two like fractions:
180/90 - 189/90 = 180 - 189/90 = -9/90 - After reducing the fraction, the answer is -1/10
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