Answers

Subtract 42/84 from 42/40

1^st number: 1 2/40, 2^nd number: 42/84

42/40 - 42/84 is 11/20.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 84 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 40 × 21 = 840,
   42/40 = 42 × 21/40 × 21 = 882/840
3. Likewise, for the 2nd fraction, since 84 × 10 = 840,
   42/84 = 42 × 10/84 × 10 = 420/840
4. Subtract the two like fractions:
   882/840 - 420/840 = 882 - 420/840 = 462/840
5. After reducing the fraction, the answer is 11/20

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