Subtract 20/49 from 81/21
1st number: 3 18/21, 2nd number: 20/49
81/21 - 20/49 is 169/49.
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,
81/21 = 81 × 7/21 × 7 = 567/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
20/49 = 20 × 3/49 × 3 = 60/147 - Subtract the two like fractions:
567/147 - 60/147 = 567 - 60/147 = 507/147 - After reducing the fraction, the answer is 169/49
- In mixed form: 322/49
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