Subtract 21/9 from 21/30
1st number: 21/30, 2nd number: 2 3/9
21/30 - 21/9 is -49/30.
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,
21/9 = 21 × 10/9 × 10 = 210/90 - Subtract the two like fractions:
63/90 - 210/90 = 63 - 210/90 = -147/90 - After reducing the fraction, the answer is -49/30
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