Answers

Subtract 70/18 from 21/45

1^st number: 21/45, 2^nd number: 3 16/18

21/45 - 70/18 is -154/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 18 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 45 × 2 = 90,
   21/45 = 21 × 2/45 × 2 = 42/90
3. Likewise, for the 2nd fraction, since 18 × 5 = 90,
   70/18 = 70 × 5/18 × 5 = 350/90
4. Subtract the two like fractions:
   42/90 - 350/90 = 42 - 350/90 = -308/90
5. After reducing the fraction, the answer is -154/45

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