Answers

Subtract 12/40 from 42/80

42/80 - 12/40 is 9/40.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 40 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 80 × 1 = 80,
   42/80 = 42 × 1/80 × 1 = 42/80
3. Likewise, for the 2nd fraction, since 40 × 2 = 80,
   12/40 = 12 × 2/40 × 2 = 24/80
4. Subtract the two like fractions:
   42/80 - 24/80 = 42 - 24/80 = 18/80
5. After reducing the fraction, the answer is 9/40

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