Answers

Subtract 49/70 from 20/81

20/81 - 49/70 is -367/810.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 70 is 5670
   
   Next, find the equivalent fraction of both fractional numbers with denominator 5670
2. For the 1st fraction, since 81 × 70 = 5670,
   20/81 = 20 × 70/81 × 70 = 1400/5670
3. Likewise, for the 2nd fraction, since 70 × 81 = 5670,
   49/70 = 49 × 81/70 × 81 = 3969/5670
4. Subtract the two like fractions:
   1400/5670 - 3969/5670 = 1400 - 3969/5670 = -2569/5670
5. After reducing the fraction, the answer is -367/810

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