Answers

Subtract 90/4 from 21/18

1^st number: 1 3/18, 2^nd number: 22 2/4

21/18 - 90/4 is -64/3.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 4 is 36
   
   Next, find the equivalent fraction of both fractional numbers with denominator 36
2. For the 1st fraction, since 18 × 2 = 36,
   21/18 = 21 × 2/18 × 2 = 42/36
3. Likewise, for the 2nd fraction, since 4 × 9 = 36,
   90/4 = 90 × 9/4 × 9 = 810/36
4. Subtract the two like fractions:
   42/36 - 810/36 = 42 - 810/36 = -768/36
5. After reducing the fraction, the answer is -64/3

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