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An asset is worth $100$ or $110$ with equal probability. Thirty percent of traders know the value and buy if it is $110$ , sell if it is $100$ ; the rest buy or sell at random. A competitive market maker sets the ask equal to the expected value given a buy. What is the ask?

Answer with a number. Fractions, powers and expressions like 23/6 or C(52,5) are read correctly in practice.

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Reading the fill: adverse selection

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Jane Street, Optiver, Citadel Securities

An asset is worth 100100100 or 110110110 with equal probability. Thirty percent of traders know the value and buy if it is 110110110, sell if it is 100100100; the rest buy or sell at random. A competitive market maker sets the ask equal to the expected value given a buy. What is the ask?

More market making questions

An asset is worth $100$ or $110$ with equal probability. Thirty percent of traders know the value and buy if it is $110$ , sell if it is $100$ ; the rest buy or sell at random. A competitive market maker sets the ask equal to the expected value given a buy. What is the ask?