Answers

Subtract 70/21 from 90/18

1^st number: 5 0/18, 2^nd number: 3 7/21

90/18 - 70/21 is 5/3.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 21 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 18 × 7 = 126,
   90/18 = 90 × 7/18 × 7 = 630/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   70/21 = 70 × 6/21 × 6 = 420/126
4. Subtract the two like fractions:
   630/126 - 420/126 = 630 - 420/126 = 210/126
5. After reducing the fraction, the answer is 5/3
6. In mixed form: 12/3

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