tryingtosecurethebag

Hello, I am trying to make sure that I'm doing this right. Question: Determine the probability that a randomly drawn respondent has x correctly identified words where x: is greater than or equal to 8. Given : Mean of 6 and standard deviation of 2. My work...

The question: If α =.05, 2-tail, would you consider responses of 9 or more words to be a rare occurrence? Why or why not? How about a score of 10? My work: Drew a distribution with .025 and .025 at both ends and .95 in between. Then: z9=9-6/2=3/2=1.5 (Loc...

Question: For a normal distribution, use the given z-scores to find the requested probability: Probability is greater than or equal to a z score of 2. I drew a distribute (picture this: the mean of 0 set at the middle and a line drawn at 2 shaded to the r...

How do you find the area that is beyond a z-score?

Question: Find the weighted average. value f 8 8 7 12 6 10 5 4 4 3 3 0 2 0 1 1 My work: ybar= (8x8)+ (7x12) + (6x10) + (5x4)+ (4x3) + (3x0) + (2x0)+ (1x0)/ 8 (but i'm not sure). Apparently, the answer is 6.34 (according to the practice quiz but I'm not su...

Question: If a distribution has a mean of 100 and a standard deviation of 15, what value would be +2 standard deviations from the mean? How would you go about solving this? Find the z-score of 2? I know that 95% (if i'm not mistaken) covers 2 standard dev...

Question: Between test 1 (score of 230 and mean of 210 and standard deviation of 22) and test 2 (score of 80 and mean of 70 and standard deviation of 8), which one is better? Explain your reasoning. I know that test 2 is better. I am not good at giving th...

The question is asking how to calculate the confidence interval for p. The sample size/n is given and the mean of that sample size is given. The confidence interval is 90. I think I am supposed to find the p-value first but I am not sure.

What is the meaning behind critical values? Like if I have a confidence interval of 95 (in which the z-score in 1.96) and I have a value that is say 2.30.. what would this mean in relationship to the confidence interval of 95?

That is what my ta taught me. I am trying to make sense of my notes because it is confusing me.

@Reiny thank you!

I forgot to include this information but the mean in the problem was stated as 6 and the standard deviation was stated as 2.

So I got 240 and divided that by the number of values and got 30 but that is nowhere near the right answer. I also know that since the average is weighted it is not 8+12+10+4+3+0+0+1/8.

Nevermind it is test 2. Test 1= z220=220-200/21=20/21=0.95=.33 Test 2= z90=90-80/8=10/8=1.25=.40

I think the formula is square root (p)- (1-p)/ n right? But to find p do I use 1-alpha/2? Is 0.10 for confidence interval 90? Like is it 1-0.10/2=.05?