Answers

Subtract 40/10 from 18/21

1^st number: 18/21, 2^nd number: 4 0/10

18/21 - 40/10 is -22/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 10 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 21 × 10 = 210,
   18/21 = 18 × 10/21 × 10 = 180/210
3. Likewise, for the 2nd fraction, since 10 × 21 = 210,
   40/10 = 40 × 21/10 × 21 = 840/210
4. Subtract the two like fractions:
   180/210 - 840/210 = 180 - 840/210 = -660/210
5. After reducing the fraction, the answer is -22/7

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