matthewicee
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My teacher returned my homework and gave me partial credit on it and I'm wondering what I did wrong on my answers other than the 194 on the table. How would you answer this work?
Questions on my probability homework
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Dr.Peterson
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If 194 were correct, then your table would be correct.
Your answer to the third question is wrong; you misread union (or) as intersection (and). You are also wrong on the fourth (intersection), perhaps because you missed the word "not".
You are wrong on the last two questions because they are about conditional probability, so the denominator should reflect the condition. You gave the probability of cellphone and PS4, not of one given the other.
Give it another try.
Your answer to the third question is wrong; you misread union (or) as intersection (and). You are also wrong on the fourth (intersection), perhaps because you missed the word "not".
You are wrong on the last two questions because they are about conditional probability, so the denominator should reflect the condition. You gave the probability of cellphone and PS4, not of one given the other.
Give it another try.
Steven G
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For the last one you are given that the student owns a ps4, so you have a restricted sample space. Just consider the students who own a ps4 to answer the probability. Of the 158 students who own a ps4, 133 owns a cell phone. So the answer would be 133/158 (assuming the 194 was correct)