To solve this problem, we use the formula:
z = (x – u) / s
where z is the z score value which can be obtained from
the tables, x is the sample value, u is the mean = 6.3 min, and s is the std
dev = 2.2 min
at P value = 0.90, the z = 1.28, finding for x:
x = z s + u
x = 1.28 * 2.2 + 6.3
x = 9.116
at P value = 1.0, the z = 3.49, finding for x:
x = z s + u
x = 3.49 * 2.2 + 6.3
x = 13.978 ~ 14
Therefore the longest 10% calls last about 9.1 minutes to
14 minutes
Answer:
the answer for question 1 is -7
You have to find the slope and where it intercepts at
Answer:
Solution : (15, - 11)
Step-by-step explanation:
We want to solve this problem using a matrix, so it would be wise to apply Gaussian elimination. Doing so we can start by writing out the matrix of the coefficients, and the solutions ( - 5 and - 2 ) --- ( 1 )

Now let's begin by canceling the leading coefficient in each row, reaching row echelon form, as we desire --- ( 2 )
Row Echelon Form :

Step # 1 : Swap the first and second matrix rows,

Step # 2 : Cancel leading coefficient in row 2 through
,

Now we can continue canceling the leading coefficient in each row, and finally reach the following matrix.

As you can see our solution is x = 15, y = - 11 or (15, - 11).
Answer:
I believe I would be the last one D