Im guessing the first answer
163-x=-52
first subtract 163 and you get -215
now it looks like -x=-215
then the negative signs cancel out and its now x=215
When you add 12, 6, 4 and 2, you will get 24. 12 of the 24 teams wear red shirts, so for every 2 teams there would be 1 team wearing red
Answer:
50065
Step-by-step explanation:
5x500 is 2500, 5x80 is 400, 5x9 is 45. 80x500 is 40000, 80x80 is 640, 80x9 is 720. I split them all up and when you add them it makes 50065
Answer:
The 90% confidence interval for the true mean lifespan of this product is between 13.1 and 16.9 years.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 50 - 1 = 49
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 49 degrees of freedom(y-axis) and a confidence level of
. So we have T = 1.6766
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 15 - 1.9 = 13.1 years
The upper end of the interval is the sample mean added to M. So it is 15 + 1.9 = 16.9 years
The 90% confidence interval for the true mean lifespan of this product is between 13.1 and 16.9 years.