Answers

Subtract 42/45 from 20/18

1^st number: 1 2/18, 2^nd number: 42/45

20/18 - 42/45 is 8/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 45 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 18 × 5 = 90,
   20/18 = 20 × 5/18 × 5 = 100/90
3. Likewise, for the 2nd fraction, since 45 × 2 = 90,
   42/45 = 42 × 2/45 × 2 = 84/90
4. Subtract the two like fractions:
   100/90 - 84/90 = 100 - 84/90 = 16/90
5. After reducing the fraction, the answer is 8/45

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