In an essay competition, the odds in favour of competitors P, Q, R S are 1:2, 1:3, 1:4, and 1:5 respectively. Find the probability that one  then win the competitions.

Explanation

To find the probability that one of the competitors (P, Q, R, or S) wins the competition based on the given odds, we will follow these steps:

### Step 1: Understand the Odds
The odds in favor of an event are given as the ratio of the number of favorable outcomes to the number of unfavorable outcomes.

- For competitor P, the odds are 1:2. This means for every 1 favorable outcome, there are 2 unfavorable outcomes.
- For competitor Q, the odds are 1:3.
- For competitor R, the odds are 1:4.
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