Answers

Subtract 9/40 from 42/84

42/84 - 9/40 is 11/40.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 84 × 10 = 840,
   42/84 = 42 × 10/84 × 10 = 420/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   9/40 = 9 × 21/40 × 21 = 189/840
4. Subtract the two like fractions:
   420/840 - 189/840 = 420 - 189/840 = 231/840
5. After reducing the fraction, the answer is 11/40

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