Answers

Subtract 72/80 from 90/20

1^st number: 4 10/20, 2^nd number: 72/80

90/20 - 72/80 is 18/5.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 80 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 20 × 4 = 80,
   90/20 = 90 × 4/20 × 4 = 360/80
3. Likewise, for the 2nd fraction, since 80 × 1 = 80,
   72/80 = 72 × 1/80 × 1 = 72/80
4. Subtract the two like fractions:
   360/80 - 72/80 = 360 - 72/80 = 288/80
5. After reducing the fraction, the answer is 18/5
6. In mixed form: 33/5

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