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Parlay of two unequal-probability legs

A bookmaker applies a 5%5\% overround to each of two independent legs by inflating their fair implied probabilities by a factor of 1.051.05. Leg A is a true 60%60\% favorite; leg B is a true 30%30\% longshot. A parlay pays only if both win, at the product of the quoted odds.

What is the fair parlay price, what does the bookmaker offer, and what is the effective margin?

Show a hint

Quoted implied probability =1.05×= 1.05 \times fair probability, so quoted odds == fair odds /1.05/ 1.05. What does multiplying two quoted odds do to the 1.051.05 factors?

Your answer

This one is open-ended. Work it through, then check your reasoning against the full solution.

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