Answers

Subtract 18/90 from 70/21

1^st number: 3 7/21, 2^nd number: 18/90

70/21 - 18/90 is 47/15.

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,
   70/21 = 70 × 30/21 × 30 = 2100/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   18/90 = 18 × 7/90 × 7 = 126/630
4. Subtract the two like fractions:
   2100/630 - 126/630 = 2100 - 126/630 = 1974/630
5. After reducing the fraction, the answer is 47/15
6. In mixed form: 32/15

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