Answers

Subtract 70/90 from 6/21

6/21 - 70/90 is -31/63.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 90 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 21 × 30 = 630,
   6/21 = 6 × 30/21 × 30 = 180/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   70/90 = 70 × 7/90 × 7 = 490/630
4. Subtract the two like fractions:
   180/630 - 490/630 = 180 - 490/630 = -310/630
5. After reducing the fraction, the answer is -31/63

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