Answers

Subtract 90/4 from 21/10

1^st number: 2 1/10, 2^nd number: 22 2/4

21/10 - 90/4 is -102/5.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 10 and 4 is 20
   
   Next, find the equivalent fraction of both fractional numbers with denominator 20
2. For the 1st fraction, since 10 × 2 = 20,
   21/10 = 21 × 2/10 × 2 = 42/20
3. Likewise, for the 2nd fraction, since 4 × 5 = 20,
   90/4 = 90 × 5/4 × 5 = 450/20
4. Subtract the two like fractions:
   42/20 - 450/20 = 42 - 450/20 = -408/20
5. After reducing the fraction, the answer is -102/5

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