Answers

Subtract 81/80 from 40/84

1^st number: 40/84, 2^nd number: 1 1/80

40/84 - 81/80 is -901/1680.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 80 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 84 × 20 = 1680,
   40/84 = 40 × 20/84 × 20 = 800/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   81/80 = 81 × 21/80 × 21 = 1701/1680
4. Subtract the two like fractions:
   800/1680 - 1701/1680 = 800 - 1701/1680 = -901/1680

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