Answers

Subtract 49/21 from 70/90

1^st number: 70/90, 2^nd number: 2 7/21

70/90 - 49/21 is -14/9.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 21 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   70/90 = 70 × 7/90 × 7 = 490/630
3. Likewise, for the 2nd fraction, since 21 × 30 = 630,
   49/21 = 49 × 30/21 × 30 = 1470/630
4. Subtract the two like fractions:
   490/630 - 1470/630 = 490 - 1470/630 = -980/630
5. After reducing the fraction, the answer is -14/9

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