Answers

Subtract 45/42 from 63/80

1^st number: 63/80, 2^nd number: 1 3/42

63/80 - 45/42 is -159/560.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 42 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 80 × 21 = 1680,
   63/80 = 63 × 21/80 × 21 = 1323/1680
3. Likewise, for the 2nd fraction, since 42 × 40 = 1680,
   45/42 = 45 × 40/42 × 40 = 1800/1680
4. Subtract the two like fractions:
   1323/1680 - 1800/1680 = 1323 - 1800/1680 = -477/1680
5. After reducing the fraction, the answer is -159/560

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