Subtract 18/9 from 21/49
1st number: 21/49, 2nd number: 2 0/9
21/49 - 18/9 is -11/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 9 is 441
Next, find the equivalent fraction of both fractional numbers with denominator 441 - For the 1st fraction, since 49 × 9 = 441,
21/49 = 21 × 9/49 × 9 = 189/441 - Likewise, for the 2nd fraction, since 9 × 49 = 441,
18/9 = 18 × 49/9 × 49 = 882/441 - Subtract the two like fractions:
189/441 - 882/441 = 189 - 882/441 = -693/441 - After reducing the fraction, the answer is -11/7
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