Test C (Station 4) Probability Word Problems and Formulas

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@jasmineworld4813 2 жыл бұрын

Thank u I’m really grateful because I’m taking my math 7th staar test today and I really wanna make my teacher proud so I woke up at 4 in the morning watching these vids

@MrHelpfulNotHurtful 2 жыл бұрын

You rock! Keep up the good work. 😊

@divinestarfire5422 Жыл бұрын

I got my test in an hour, these videos are super helpful you explain probability so well. also i loved the part you said “ Fe= not iron but it makes sense because women are strong” 😂

@MrHelpfulNotHurtful Жыл бұрын

Good luck on your test!! I’m glad I could support the cause. Also, I appreciate your feedback. 😎

@dieulinhnguyen8323 Жыл бұрын

amazing! Thank u so much! After watching 2 of ur videos about probability I'm becoming more confident in this topic!

@MrHelpfulNotHurtful Жыл бұрын

Yay! So glad I could help. 😊

@mjev78 Жыл бұрын

Wouldn't the probability of being French and female be 10/60 or 16.7%, given 60 of 100 are French and 10 of the French are female?

@MrHelpfulNotHurtful Жыл бұрын

Here are two situations that sound similar, but are not the same. Situation A: find the probability of randomly selecting a female given that she is French. This is what you are calculating when you do 10/60.Situation B: find the probability of randomly selecting a person who is female and French. This is the situation in the question. Imagine that you have all of the 100 names on cards mixed in a bin. Situation B would be like if your friend pulled out one name at random and sealed it in an envelope and then asked you to calculate the probability that the person in the envelope is female and French (female/100)(French/100). Situation A would be like if your friend pulled a name at random and put it in the envelope and said, “The person in the envelope is French. Calculate the probability that the person in the envelope is female.” Because your are given the additional information that the person is French, you can narrow it down to 60 people who are French and 10 of them are female, so 10/60. In the question in the video, Situation B, you are not told in advance that the person in the envelope is female. You are blind to both gender and nationality, as you calculate the probability that the person in the envelope is female and French, so can’t narrow it down to 60 people, you have to calculate each probability (female, French) using the full 100 and then multiply. This is a tough concept. I hope this explanation helps.

@camilledelacruz6418 2 жыл бұрын

Can you help me in solving this problem? Rey joined the shampoo for a caused civil group as an athlete advocate, he voluntary accepted the task of handy out free samples of shampoo at random to the participants of the shampoo day mini convention. He was instructed to stop handling free samples only with he had at already given exactly 10 free samples of shampoo to male participants. Suppose that there are 142 females and 78 males present in the mini convention. What is the probability that the 10th and last male recipient of free shampoo is also the 35th recipient of free samples? The correct answer is 0.02905 but I don't know how to arrive with that answer.

@MrHelpfulNotHurtful 2 жыл бұрын

I’m sorry. I don’t know how to do this one. 😔

@Kjoripisitrogognapry 5 ай бұрын

To solve this problem, we can use the concept of conditional probability. Let's define the events: - Event A: The 10th and last male recipient of free shampoo is also the 35th recipient of free samples. - Event B: Rey gives free shampoo to a male participant. Given: - Total number of participants = 142 (females) + 78 (males) = 220 - Rey stops giving free samples after giving exactly 10 free samples to male participants. We need to find the probability of Event A given Event B has occurred. The probability of Event B (Rey gives free shampoo to a male participant) is the probability of selecting a male participant, which is \( \frac{78}{220} = \frac{39}{110} \). Now, let's calculate the probability of Event A: - The probability that the 10th male recipient of free shampoo is also the 35th recipient is \( \frac{1}{78} \) because there is only one 10th and last male recipient. - The probability that the other 9 male recipients are not the 35th recipient is \( \frac{77}{78} \) for each of them. Therefore, the probability of Event A is: \[ P(A) = \left( \frac{1}{78} ight) \times \left( \frac{77}{78} ight)^9 \] Now, we multiply the probability of Event A by the probability of Event B to get the final answer: \[ P(A \cap B) = P(A) \times P(B) = \left( \frac{1}{78} ight) \times \left( \frac{77}{78} ight)^9 \times \frac{39}{110} \] By calculating this expression, we should arrive at the correct answer of approximately 0.02905.

@ashkanmirani2625 Жыл бұрын

OK, in the first question, why isn't the probability of picking a French, female student just 1 out of 10? Since the question already mentions there being 10 French students who are female, and that there are 100 students overall.

@MrHelpfulNotHurtful Жыл бұрын

The following two questions are not calculated the same way: 1) What is the probability of selecting a student who is female and French? 2) What is the probability of selecting a female student given that the student is French. In #1 the probability is indeed 10/100 (Target/Total). However, in #2, the statement “given that the student is French” changes the total. We now consider ONLY the French students as the total. The question is now equivalent to asking the probability of selecting a female student out of a group made of only the French students. 10/60 (Target/NewTotal). 😎

@ashkanmirani2625 Жыл бұрын

@@MrHelpfulNotHurtful thank you