Answer:
1.5 km
Step-by-step explanation:
Length of pool = 25m
no.of lengths. = 60
Total length of he swim s = 25m* 60
= 1500m
You know , 1000m = 1km ,
so,
He swims 1500m/1000m
= 1.5 km
Answer:
N = 9
M = 87.11
Step-by-step explanation:
According to the situation, the data provided and the solution are as follows
The scores for the student in the classroom is
= 88 88 92 88 88 72 96 88 84
The different student's number of scores is 9
The solution of new n and M is shown below:-
Sample size (n) = 9
Sample mean (m) is

= 

= 87.11
Answer:
The 90% confidence interval for the mean score of all takers of this test is between 59.92 and 64.08. The lower end is 59.92, and the upper end is 64.08.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 62 - 2.08 = 59.92
The upper end of the interval is the sample mean added to M. So it is 62 + 2.08 = 64.08.
The 90% confidence interval for the mean score of all takers of this test is between 59.92 and 64.08. The lower end is 59.92, and the upper end is 64.08.
2y-6=34 is the needed equation