Subtract 28/10 from 21/9
1st number: 2 3/9, 2nd number: 2 8/10
21/9 - 28/10 is -7/15.
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,
21/9 = 21 × 10/9 × 10 = 210/90 - Likewise, for the 2nd fraction, since 10 × 9 = 90,
28/10 = 28 × 9/10 × 9 = 252/90 - Subtract the two like fractions:
210/90 - 252/90 = 210 - 252/90 = -42/90 - After reducing the fraction, the answer is -7/15
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