Answers

Subtract 40/21 from 10/18

1^st number: 10/18, 2^nd number: 1 19/21

10/18 - 40/21 is -85/63.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 21 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 18 × 7 = 126,
   10/18 = 10 × 7/18 × 7 = 70/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   40/21 = 40 × 6/21 × 6 = 240/126
4. Subtract the two like fractions:
   70/126 - 240/126 = 70 - 240/126 = -170/126
5. After reducing the fraction, the answer is -85/63

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