Answers

Subtract 63/81 from 42/30

1^st number: 1 12/30, 2^nd number: 63/81

42/30 - 63/81 is 28/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 81 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 30 × 27 = 810,
   42/30 = 42 × 27/30 × 27 = 1134/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   63/81 = 63 × 10/81 × 10 = 630/810
4. Subtract the two like fractions:
   1134/810 - 630/810 = 1134 - 630/810 = 504/810
5. After reducing the fraction, the answer is 28/45

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