Answers

Subtract 72/81 from 90/60

1^st number: 1 30/60, 2^nd number: 72/81

90/60 - 72/81 is 11/18.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 60 and 81 is 1620
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1620
2. For the 1st fraction, since 60 × 27 = 1620,
   90/60 = 90 × 27/60 × 27 = 2430/1620
3. Likewise, for the 2nd fraction, since 81 × 20 = 1620,
   72/81 = 72 × 20/81 × 20 = 1440/1620
4. Subtract the two like fractions:
   2430/1620 - 1440/1620 = 2430 - 1440/1620 = 990/1620
5. After reducing the fraction, the answer is 11/18

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