Subtract 42/49 from 42/21
1st number: 2 0/21, 2nd number: 42/49
42/21 - 42/49 is 8/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147
Next, find the equivalent fraction of both fractional numbers with denominator 147 - For the 1st fraction, since 21 × 7 = 147,
42/21 = 42 × 7/21 × 7 = 294/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
42/49 = 42 × 3/49 × 3 = 126/147 - Subtract the two like fractions:
294/147 - 126/147 = 294 - 126/147 = 168/147 - After reducing the fraction, the answer is 8/7
- In mixed form: 11/7
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