Answers

Subtract 42/84 from 1/15

1/15 - 42/84 is -13/30.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 15 and 84 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 15 × 28 = 420,
   1/15 = 1 × 28/15 × 28 = 28/420
3. Likewise, for the 2nd fraction, since 84 × 5 = 420,
   42/84 = 42 × 5/84 × 5 = 210/420
4. Subtract the two like fractions:
   28/420 - 210/420 = 28 - 210/420 = -182/420
5. After reducing the fraction, the answer is -13/30

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