Answers

Subtract 21/18 from 42/90

1^st number: 42/90, 2^nd number: 1 3/18

42/90 - 21/18 is -7/10.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 18 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 90 × 1 = 90,
   42/90 = 42 × 1/90 × 1 = 42/90
3. Likewise, for the 2nd fraction, since 18 × 5 = 90,
   21/18 = 21 × 5/18 × 5 = 105/90
4. Subtract the two like fractions:
   42/90 - 105/90 = 42 - 105/90 = -63/90
5. After reducing the fraction, the answer is -7/10

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