Answers

Subtract 18/80 from 42/20

1^st number: 2 2/20, 2^nd number: 18/80

42/20 - 18/80 is 15/8.

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,
   42/20 = 42 × 4/20 × 4 = 168/80
3. Likewise, for the 2nd fraction, since 80 × 1 = 80,
   18/80 = 18 × 1/80 × 1 = 18/80
4. Subtract the two like fractions:
   168/80 - 18/80 = 168 - 18/80 = 150/80
5. After reducing the fraction, the answer is 15/8
6. In mixed form: 17/8

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