Answers

Subtract 90/18 from 42/45

1^st number: 42/45, 2^nd number: 5 0/18

42/45 - 90/18 is -61/15.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 18 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 45 × 2 = 90,
   42/45 = 42 × 2/45 × 2 = 84/90
3. Likewise, for the 2nd fraction, since 18 × 5 = 90,
   90/18 = 90 × 5/18 × 5 = 450/90
4. Subtract the two like fractions:
   84/90 - 450/90 = 84 - 450/90 = -366/90
5. After reducing the fraction, the answer is -61/15

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