Answers

Subtract 18/80 from 30/40

30/40 - 18/80 is 21/40.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 80 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 40 × 2 = 80,
   30/40 = 30 × 2/40 × 2 = 60/80
3. Likewise, for the 2nd fraction, since 80 × 1 = 80,
   18/80 = 18 × 1/80 × 1 = 18/80
4. Subtract the two like fractions:
   60/80 - 18/80 = 60 - 18/80 = 42/80
5. After reducing the fraction, the answer is 21/40

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