Based on a random sample of size 50, you observe a sample mean of 143.6 and a sample standard deviation of 38.1. You then calculate a 95% confidence interval for the population mean, and it has length L1. Now suppose that the sample size had instead been 150, but with the same sample mean and the same sample standard deviation. Let L2 be the length of a 95% confidence interval for the population mean based on this larger sample. Which of the following is closest to the ratio L2/L1? a. 0.78
b. 0.57
c. 0.86
d. 0.65

assuming you mean addition: addition and subtraction are reverse operations.

step-by-step explanation:

he used the algebra tiles correctly.

step-by-step explanation:

given : 3x(2x-1)

solution :

since he used algebra tiles .

armando's solution is the same in the solution shown in figure

as he distributed 2x into x and x and wrote them vertically

and also write   -1 vertically

and 3x into x and x and x and wrote it horizontally

performing the multiplication in the algebra tiles we get

and solving the given expression :

3x(2x-1)

since solving the expression using tiles   and solving the expression algebraically we get the same answer

thus   we can choose the first statement as the answer to this problem which is "he used the algebra tiles correctly".

78.59 is the mean

step-by-step explanation: