Answers

Subtract 54/72 from 42/20

1^st number: 2 2/20, 2^nd number: 54/72

42/20 - 54/72 is 27/20.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 72 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 20 × 18 = 360,
   42/20 = 42 × 18/20 × 18 = 756/360
3. Likewise, for the 2nd fraction, since 72 × 5 = 360,
   54/72 = 54 × 5/72 × 5 = 270/360
4. Subtract the two like fractions:
   756/360 - 270/360 = 756 - 270/360 = 486/360
5. After reducing the fraction, the answer is 27/20
6. In mixed form: 17/20

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