Answers

Subtract 21/18 from 8/5

1^st number: 1 3/5, 2^nd number: 1 3/18

8/5 - 21/18 is 13/30.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 5 and 18 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 5 × 18 = 90,
   8/5 = 8 × 18/5 × 18 = 144/90
3. Likewise, for the 2nd fraction, since 18 × 5 = 90,
   21/18 = 21 × 5/18 × 5 = 105/90
4. Subtract the two like fractions:
   144/90 - 105/90 = 144 - 105/90 = 39/90
5. After reducing the fraction, the answer is 13/30

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