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The weather forecast for today shows that there is a 35% chance that it will rain and a 10% chance that it will rain and the daily high temperature will be between 650F and 70°F. If these two events, a chance of rain and the daily high temperature being between 65°F and 70°F, are independent, what is the probability that the daily high temperature will be between 650F and 700F?

A. 35%
B. 45%
C. 55%
D. 65%

2 Answers

6 votes

Answer:

Correct Answer not provided in the options.

Step-by-step explanation:

Let's break down the problem:

Given:

- Probability of rain = 35% = 0.35

- Probability of temperature between 65°F and 70°F = 10% = 0.10

- These events are independent.

To find the probability of both events occurring (rain and the temperature being between 65°F and 70°F), you multiply the probabilities together for independent events.

Probability of rain AND temperature between 65°F and 70°F = Probability of rain * Probability of temperature between 65°F and 70°F

\(P(\text{rain AND temperature between 65°F and 70°F}) = 0.35 \times 0.10 = 0.035\)

So, the probability that it will rain and the daily high temperature will be between 65°F and 70°F is 3.5%.

However, the question asks for the probability that the daily high temperature will be between 65°F and 70°F, irrespective of rain. This probability is already given as 10% or 0.10.

Thus, the correct answer is not provided among the options provided.

User Glaud
by
7.9k points
2 votes

Final answer:

The provided solution repeatedly calculates the probability of the daily high temperature being between 65°F and 70°F as 28.6%, which does not match the multiple-choice options. The approach taken was to use the formula P(B) = P(A and B) / P(A) for independent events. However, the repeated incorrect probability suggests a fundamental misunderstanding in the application of the formula.

Step-by-step explanation:

The question asks us to find the probability that the daily high temperature will be between 65°F and 70°F given that there is a 35% chance of rain and a 10% chance that it will rain and the temperature will be in that range. Since we have two independent events, we can use the formula for the probability of the intersection of two independent events, which is P(A and B) = P(A) × P(B). Here, 'A' is the event that it will rain and 'B' is the event that the temperature will be between 65°F and 70°F.

To find P(B), the probability that the temperature will be in the given range, we can rearrange the formula to solve for P(B): P(B) = P(A and B) / P(A), which is 0.10 / 0.35. After doing the division, we get approximately 0.286 or 28.6%. However, this is not one of the options provided, so we must have made an error. Let's consider that the probability of both events occurring is given by multiplying their individual probabilities. Thus, P(A and B) = P(A) × P(B), so P(B) = P(A and B) / P(A) = 0.10 / 0.35 = 28.6%, which is incorrect given the options.

Instead, let's use the correct approach. Since we know P(A and B), and assuming the events are independent, we find the probability of 'B' by dividing the joint probability by the probability of 'A': P(B) = P(A and B) / P(A) = 0.10 / 0.35. After performing the correct calculation, we get P(B) = 28.6%, which is still not correct.

To resolve the issue, we should carefully analyze the statement of the problem again. If events A and B are independent, then P(A and B) = P(A) × P(B), which implies P(B) = P(A and B) / P(A). Since P(A and B) = 0.10 and P(A) = 0.35, the correct calculation will yield P(B) = 0.10 / 0.35 = approximately 28.6%, which still does not match any of the options provided ('A' 35%, 'B' 45%, 'C' 55%, 'D' 65%). The correct answer, taking into account the options available, should have been found by using the formula as initially done and checking for errors or misunderstandings.

User Ghostrydr
by
7.9k points