Answers

Subtract 70/18 from 21/15

1^st number: 1 6/15, 2^nd number: 3 16/18

21/15 - 70/18 is -112/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 15 and 18 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 15 × 6 = 90,
   21/15 = 21 × 6/15 × 6 = 126/90
3. Likewise, for the 2nd fraction, since 18 × 5 = 90,
   70/18 = 70 × 5/18 × 5 = 350/90
4. Subtract the two like fractions:
   126/90 - 350/90 = 126 - 350/90 = -224/90
5. After reducing the fraction, the answer is -112/45

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