Answers

Subtract 28/10 from 42/80

1^st number: 42/80, 2^nd number: 2 8/10

42/80 - 28/10 is -91/40.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 10 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 10 × 8 = 80,
   28/10 = 28 × 8/10 × 8 = 224/80
4. Subtract the two like fractions:
   42/80 - 224/80 = 42 - 224/80 = -182/80
5. After reducing the fraction, the answer is -91/40

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