Answers

Subtract 45/8 from 90/20

1^st number: 4 10/20, 2^nd number: 5 5/8

90/20 - 45/8 is -9/8.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 8 is 40
   
   Next, find the equivalent fraction of both fractional numbers with denominator 40
2. For the 1st fraction, since 20 × 2 = 40,
   90/20 = 90 × 2/20 × 2 = 180/40
3. Likewise, for the 2nd fraction, since 8 × 5 = 40,
   45/8 = 45 × 5/8 × 5 = 225/40
4. Subtract the two like fractions:
   180/40 - 225/40 = 180 - 225/40 = -45/40
5. After reducing the fraction, the answer is -9/8

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