Recent content by xsgx

Wow.. I can't believe I missed that. Thank you.

I just need someone to confirm my answer so I can be certain that my book has a typo and I am not making a some minuscule mistake that is leading me to the wrong answer. A piece of metal is heated to 300 degrees Celsius and then placed in a cooling liquid at 50 degrees Celsius. After 4...

I will be sure to follow the template and to include the question in my next post.

Revised answer: The null hypothesis is that the mean weight of Caucasian babies is the same as the mean weight for Chinese babies Ho: M = 3369, and the alternative hypothesis is that the mean weight for Chinese babies is less so H1: M<3369. For the first step I calculated the test statistic for...

Well the question is sort of self evident isn't it? Does my explanation contain any errors?

The problem: A simple random sample of 1862 births of Chinese babies resulted in a mean birth weight of 3171 g and a standard deviation of 428 g (based on “Comparison of Birth Weight Distributions between Chinese and Caucasian Infants,” by Wen et al., American Journal of Epidemiology, Vol.172...

^^ In that case would this be a satisfactory answer? For the first step I calculated P^ by dividing the amount of people who responded that they do have enough leisure time by the sample size: this gave me a P^ value of .65 after rounding. Since there is already an established claim that ⅔ of...

For the first step I calculated P by dividing the amount of people who responded that they do have enough leisure time by the sample size: this gave me a P value of .65 after rounding. Since there is no previously known value of P this becomes the null hypothesis . The ⅔ of adults claim then...

My guess is that the null hypothesis is Ho=.65 and the alternative hypothesis is h1>.65. But I want to be sure.

Leisure Time In a Gallup poll: 1010 adults were randomly selected and asked if they were satisfied or dissatisfied with the amount of leisure time that they had. Of this sample 657 said that they were satisfied and 353 said that they were dissatisfied. Use a 0.01 significance level to test the...

Sorry I forgot to say that I took the square root of the answer 0.081. Anyways I have solved this problem. This thread can be closed.

^ Actually that's exactly what I needed to do haha. I don't quite understand why it works that way though. Can anyone explain it?

Both my book and the Wikipedia link gives the same formula for calculating the error of the mean: Error of the mean= variance/sample size. When I do the calculations I get . I don't see how I can apply that number to solving this problem. Is this the new standard deviation that I use to...

I just found the equation in my book they dedicated such a little piece of text to it that I missed it when reading the first time. I calculated the standard error to of the mean to be Where do I go from this step?

That is where I am stuck and unsure of what to do. Do I raise the probability of getting one mechanic whose time exceeds 8.7 to the power of 40? So that would be ?