Subtract 12/9 from 21/30
1st number: 21/30, 2nd number: 1 3/9
21/30 - 12/9 is -19/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 9 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 9 × 10 = 90,
12/9 = 12 × 10/9 × 10 = 120/90 - Subtract the two like fractions:
63/90 - 120/90 = 63 - 120/90 = -57/90 - After reducing the fraction, the answer is -19/30
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