Answers

Subtract 35/20 from 72/90

1^st number: 72/90, 2^nd number: 1 15/20

72/90 - 35/20 is -19/20.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 20 is 180
   
   Next, find the equivalent fraction of both fractional numbers with denominator 180
2. For the 1st fraction, since 90 × 2 = 180,
   72/90 = 72 × 2/90 × 2 = 144/180
3. Likewise, for the 2nd fraction, since 20 × 9 = 180,
   35/20 = 35 × 9/20 × 9 = 315/180
4. Subtract the two like fractions:
   144/180 - 315/180 = 144 - 315/180 = -171/180
5. After reducing the fraction, the answer is -19/20

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