Subtract 21/9 from 42/49
1st number: 42/49, 2nd number: 2 3/9
42/49 - 21/9 is -31/21.
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,
42/49 = 42 × 9/49 × 9 = 378/441 - Likewise, for the 2nd fraction, since 9 × 49 = 441,
21/9 = 21 × 49/9 × 49 = 1029/441 - Subtract the two like fractions:
378/441 - 1029/441 = 378 - 1029/441 = -651/441 - After reducing the fraction, the answer is -31/21
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