Subtract 21/9 from 30/18
1st number: 1 12/18, 2nd number: 2 3/9
30/18 - 21/9 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 9 is 18
Next, find the equivalent fraction of both fractional numbers with denominator 18 - For the 1st fraction, since 18 × 1 = 18,
30/18 = 30 × 1/18 × 1 = 30/18 - Likewise, for the 2nd fraction, since 9 × 2 = 18,
21/9 = 21 × 2/9 × 2 = 42/18 - Subtract the two like fractions:
30/18 - 42/18 = 30 - 42/18 = -12/18 - After reducing the fraction, the answer is -2/3
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