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Predict in 40 spins how many times you would spin a number less than 8.

a) 7
b) 10
c) 12
d) 15

User Tototoshi
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1 Answer

3 votes

Final answer:

Using a standard roulette wheel with numbers 1 to 36, you would expect to land on a number less than 8 about 7/36 of the time. For 40 spins, this would be 7.77 times, rounded to 8 times. Thus, answer (b) 10 is the closest estimate to the expected outcome.

Step-by-step explanation:

In order to predict how many times you would spin a number less than 8 in 40 spins, assume that you are using a standard roulette wheel with numbers from 1 to 36, plus 0 (and 00 in American roulette). Since there are 7 numbers (1 through 6 and 0) which are less than 8, and assuming a uniform probability distribution, the chance of landing on a number less than 8 on any given spin is 7 out of 37 (or 38 if considering American roulette with the '00'). However, for simplification, we will use 1 to 36 range.

If each number has an equal chance of being landed on, you would expect to land on a number less than 8 approximately 7/36 of the time. To predict the number in 40 spins, multiply the probability by the number of spins: (7/36) × 40 = 7 × (40/36) ≈ 7 × 1.11 = 7.77, so you can predict that you would land on a number less than 8 around 8 times, so answer (b) 10 is the closest.

User Markych
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