Answer:
The margin of error of the 90% confidence interval of a student's average typing speed is of 1.933 wpm.
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 = 20 - 1 = 19
90% 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 = 1.7291
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample. For this question, we have
. So



The margin of error of the 90% confidence interval of a student's average typing speed is of 1.933 wpm.
If the price after the discount is subtracted is $96.25 then this is what you do
u times 0.40 x 96.25 which is 38.5 so since you are wanting to know what the price was before the discount you would add 38.5 to 96.25 and when you do that your answer is 134.75
but if you are just trying to get the discount from 96.25 you subtract 38.5 from 96.25
Answer:
c
Step-by-step explanation:
its c
C=480
solve
480=24n+35
minus 35 both sides
445=24n
divide both sides by 24
18.541666666666666666666666666667=n
<span>so about 18 cakes</span>