Answers

Subtract 36/40 from 30/80

30/80 - 36/40 is -21/40.

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,
   30/80 = 30 × 1/80 × 1 = 30/80
3. Likewise, for the 2nd fraction, since 40 × 2 = 80,
   36/40 = 36 × 2/40 × 2 = 72/80
4. Subtract the two like fractions:
   30/80 - 72/80 = 30 - 72/80 = -42/80
5. After reducing the fraction, the answer is -21/40

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