问题


There is a single choice question about high school statistics. Answer the question by replying A, B, C or D.
Question: Two dice are rolled simultaneously. If both dice show 6, then the player wins $20; otherwise the player loses the game. It costs $2.00 to play the game. What is the expected gain or loss per game?
A. The player will gain about $0.55.
B. The player will gain about $1.44.
C. The player will lose about $0.55.
D. The player will lose about $1.44.
Answer:

答案

模型 模型答案 正确答案
金声玉亮2.0

A nice statistics question!

Let's break it down:

* The probability of both dice showing 6 is (1/6) × (1/6) = 1/36, since each die has 6 possible outcomes.
* The probability of not getting both 6's is 1 - 1/36 = 35/36.
* If the player wins, they gain $20 - $2 (cost to play) = $18.
* If the player loses, they lose $2 (cost to play).

Now, let's calculate the expected value:

Expected Value = (Probability of winning × Gain) + (Probability of losing × Loss)
= (1/36 × $18) + (35/36 × -$2)
= $0.50 - $1.94
= -$1.44

So, the player can expect to lose approximately $1.44 per game.

Answer: D.
D
deepseekr1

The expected value is calculated by considering the probabilities and outcomes. Rolling two dice has 36 possible outcomes, with only one resulting in both showing a 6 (probability = 1/36). Winning yields $20, but the $2 cost to play is subtracted regardless of the outcome.

**Calculation**:
- Expected winnings: \( \frac{1}{36} \times 20 = \frac{20}{36} \approx 0.5556 \).
- Subtract the $2 cost: \( 0.5556 - 2 \approx -1.4444 \).

This results in an **expected loss of approximately $1.44 per game**.

**Answer**: D. The player will lose about $1.44.
D
gpto1 D D
GPT-4o To determine the expected gain or loss per game, we need to calculate the expected value of the game.

1. **Probability of Winning**: The probability of rolling a 6 on one die is \( \frac{1}{6} \). Therefore, the probability of both dice showing 6 is:
\[ \left(\frac{1}{6}\right) \times \left(\frac{1}{6}\right) = \frac{1}{36} \]

2. **Probability of Losing**: The probability of not rolling double sixes is:
\[ 1 - \frac{1}{36} = \frac{35}{36} \]

3. **Gain/Loss Amounts**:
- If the player wins, they gain $20 but have also paid $2 to play, so the net gain is \( \$20 - \$2 = \$18 \).
- If the player loses, they lose the $2 cost of playing, so the net loss is \( -\$2 \).

4. **Expected Value Calculation**:
\[ \text{Expected Value} = (\text{Probability of Winning} \times \text{Net Gain}) + (\text{Probability of Losing} \times \text{Net Loss}) \]
\[ = \left(\frac{1}{36} \times 18\right) + \left(\frac{35}{36} \times -2\right) \]
\[ = \left(\frac{18}{36}\right) + \left(\frac{-70}{36}\right) \]
\[ = \frac{18 - 70}{36} \]
\[ = \frac{-52}{36} \]
\[ = -\frac{26}{18} \]
\[ = -\frac{13}{9} \approx -1.44 \]

So, the expected loss per game is about $1.44. Therefore, the correct answer is:

D. The player will lose about $1.44.
D
llama3.1-70B-Instruct

The correct answer is C.
D
llama3.1-405B-Instruct

A

Explanation:
The probability of winning is 1/36, and the probability of losing is 35/36. The expected gain or loss per game is calculated as follows:

Expected gain or loss = (probability of winning x amount won) - (probability of losing x amount lost)
= (1/36 x $20) - (35/36 x $2)
= $0.55 - $1.94
= -$1.39

Since the expected gain or loss is negative, the player will lose about $1.39 per game on average. However, the closest answer choice is A, which states that the player will gain about $0.55. This is incorrect, as the player will actually lose money on average.
D
DeepSeek-Coder-V2 C D
Qwen2-72B-Instruct C. The player will lose about $0.55. D
baichuan4 C D
doubao The probability of both dice showing 6 is 1/36. The gain when this happens is $20 - $2 = $18. The probability of not getting both 6 is 35/36 and the loss is $2. The expected value = (1/36) * $18 + (35/36) * (-2) = -11 / 18 ≈ -0.61. So the player will lose about $0.61, which is closest to C. The player will lose about $0.55.
So the answer is C.
D
minimax To calculate the expected gain or loss per game, we need to consider the probability of winning and the probability of losing.

There is only one way to roll a double six (6,6), but there are 6 sides on each die, so there are a total of 6 * 6 = 36 possible outcomes when rolling two dice.

The probability of winning is the probability of rolling a double six, which is 1/36. The probability of losing is the probability of not rolling a double six, which is 35/36.

The expected value (EV) is calculated by multiplying the outcomes by their respective probabilities and summing them up:

EV = (Probability of Winning * Amount Won) - (Probability of Losing * Cost to Play)

EV = (1/36 * $20) - (35/36 * $2)

EV = ($20/36) - ($70/36)

EV = ($20 - $70) / 36

EV = -$50 / 36

EV = -$1.3888...

The closest answer to this expected loss is:

D. The player will lose about $1.44.
D
kimi To calculate the expected gain or loss per game, we need to consider the probability of winning and the payout, as well as the cost to play.

The probability of rolling a 6 on a single die is 1/6. Since the dice are rolled simultaneously and independently, the probability of both dice showing a 6 is the product of the individual probabilities:

\[ P(\text{both dice show 6}) = \left(\frac{1}{6}\right) \times \left(\frac{1}{6}\right) = \frac{1}{36} \]

The payout for winning is $20, and the cost to play is $2.00. The expected value (EV) of the game can be calculated as follows:

\[ EV = (P(\text{win}) \times \text{winnings}) - (\text{cost to play}) \]
\[ EV = \left(\frac{1}{36} \times 20\right) - 2 \]
\[ EV = \frac{20}{36} - 2 \]
\[ EV = \frac{5}{9} - 2 \]
\[ EV = 0.555... - 2 \]
\[ EV = -1.444... \]

This means that on average, the player can expect to lose about $1.44 per game.

Answer: D. The player will lose about $1.44.
D
wenxinyiyan D D
zhipu To determine the expected gain or loss per game, we need to calculate the expected value of the game.

1. **Probability of Winning:**
- The probability of rolling a 6 on a single die is \( \frac{1}{6} \).
- The probability of rolling a 6 on both dice simultaneously is \( \frac{1}{6} \times \frac{1}{6} = \frac{1}{36} \).

2. **Probability of Losing:**
- The probability of not rolling a 6 on both dice is \( 1 - \frac{1}{36} = \frac{35}{36} \).

3. **Payoffs:**
- If the player wins (both dice show 6), they receive $20.
- If the player loses, they lose the $2 they paid to play.

4. **Expected Value Calculation:**
- The expected value (EV) can be calculated using the formula:
\[
EV = (P_{\text{win}} \times \text{Winning Amount}) + (P_{\text{lose}} \times \text{Losing Amount})
\]
- Substituting the values:
\[
EV = \left( \frac{1}{36} \times 20 \right) + \left( \frac{35}{36} \times (-2) \right)
\]
- Calculating each term:
\[
EV = \left( \frac{20}{36} \right) + \left( \frac{-70}{36} \right)
\]
- Simplifying:
\[
EV = \frac{20 - 70}{36} = \frac{-50}{36} \approx -1.39
\]

So, the expected loss per game is approximately $1.39, which is closest to $1.44.

Therefore, the correct answer is:
D. The player will lose about $1.44.
D
gpto1 D D
deepseekv3 To determine the expected gain or loss per game, follow these steps:

1. **Calculate the probability of winning:**
- When two dice are rolled, there are \(6 \times 6 = 36\) possible outcomes.
- There is only **1** outcome where both dice show a 6 (i.e., (6, 6)).
- So, the probability of winning is \(\frac{1}{36}\).

2. **Calculate the probability of losing:**
- Since there is only 1 winning outcome, the probability of losing is \(1 - \frac{1}{36} = \frac{35}{36}\).

3. **Calculate the expected value:**
- If the player wins, they gain \(20 - 2 = \$18\) (since it costs \$2 to play).
- If the player loses, they lose \$2.
- The expected value \(E\) is calculated as:
\[
E = \left(\frac{1}{36} \times 18\right) + \left(\frac{35}{36} \times (-2)\right)
\]
\[
E = \frac{18}{36} - \frac{70}{36}
\]
\[
E = \frac{-52}{36} \approx -1.44
\]

4. **Interpret the result:**
- The expected value is approximately \(-\$1.44\), meaning the player is expected to lose about \$1.44 per game.

**Answer:** D. The player will lose about $1.44.
D