Answers

Subtract 70/15 from 21/18

1^st number: 1 3/18, 2^nd number: 4 10/15

21/18 - 70/15 is -7/2.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 15 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 18 × 5 = 90,
   21/18 = 21 × 5/18 × 5 = 105/90
3. Likewise, for the 2nd fraction, since 15 × 6 = 90,
   70/15 = 70 × 6/15 × 6 = 420/90
4. Subtract the two like fractions:
   105/90 - 420/90 = 105 - 420/90 = -315/90
5. After reducing the fraction, the answer is -7/2

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