Answers

Subtract 1/40 from 40/42

40/42 - 1/40 is 779/840.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 42 × 20 = 840,
   40/42 = 40 × 20/42 × 20 = 800/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   1/40 = 1 × 21/40 × 21 = 21/840
4. Subtract the two like fractions:
   800/840 - 21/840 = 800 - 21/840 = 779/840

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