Answer:
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution 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 = 20 - 1 = 19
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 19 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 2.861.
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The format of the confidence interval is:
In which 
is the sample mean
So
She can make only four necklaces:
86/18 = 4.77777
but that .7777 wont make a whole necklace so she can only make 4 full necklaces
Answer:
wdee
Step-by-step explanation:
fcecfefve
Answer:
95:95:19
Step-by-step explanation:
1.Divide 209 by 11.(209÷19)
2.Multiply 19×5 since 5/11 of the coins are nickels.(19×5=95)
3.Multiply 19×5 again since 5/11 of the coins are dimes.(19×5=95)
4.Multiply 19×1 since there would be 1/11 left of the coins which are quarters. (19×1=19)
5.Check your awnser by adding 95+95+19.(95+95+19=209)
Answer:
-cos(2A)
Step-by-step explanation:
We know that (a+b) (a-b) = a^2-b^2
So it means we can simplify to sin^2(A)-cos^2(A) and we know cos^2(A) - sin^2(A) = cos(2A) but we will just multiply by -1 and we get - cos(2A)
