Answers

Subtract 70/21 from 45/90

1^st number: 45/90, 2^nd number: 3 7/21

45/90 - 70/21 is -17/6.

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,
   45/90 = 45 × 7/90 × 7 = 315/630
3. Likewise, for the 2nd fraction, since 21 × 30 = 630,
   70/21 = 70 × 30/21 × 30 = 2100/630
4. Subtract the two like fractions:
   315/630 - 2100/630 = 315 - 2100/630 = -1785/630
5. After reducing the fraction, the answer is -17/6

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