Subtract 21/15 from 12/9
1st number: 1 3/9, 2nd number: 1 6/15
12/9 - 21/15 is -1/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 15 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 9 × 5 = 45,
12/9 = 12 × 5/9 × 5 = 60/45 - Likewise, for the 2nd fraction, since 15 × 3 = 45,
21/15 = 21 × 3/15 × 3 = 63/45 - Subtract the two like fractions:
60/45 - 63/45 = 60 - 63/45 = -3/45 - After reducing the fraction, the answer is -1/15
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