Let
be the random variable for the number of marks a given student receives on the exam.
10% of students obtain more than 75 marks, so

where
follows a standard normal distribution. The critical value for an upper-tail probability of 10% is

where
denotes the CDF of
, and
denotes the inverse CDF. We have

Similarly, because 20% of students obtain less than 40 marks, we have

so that

Then
are such that


and we find

Answer:
Step-by-step explanation:
VW, also know as side X (as shown in image) can be found using the sine. Sin(theta)=opposite/hypotenuse. In this case, theta is 31 degrees and the hypotenuse is 31 feet. Plugging in all known values, we would have sin(31)=x/31. Rearrange the equation and isolate X on one side. Then use a calculator to find the answer. Good luck!
As the ratio of your shadow to your height is 2:1 assuming the flagpole would form a similar triangle the shadow is twice the height of the pole meaning the pole is 14 feet tall
For the statement "....A 4-column table with 3 rows. The first column has no label with entries internet, cable television, or total. The second column is labeled satisfied with entries ..." statement about the two-way frequency table that is true is About one-fourth of the cable-television customers are not satisfied. Option D.
This is further explained below.
<h3>What is a two-way frequency table?</h3>
Generally, A two-way table may be used to show the frequency of occurrence of two categories. A row represents a single category, whereas a column represents a different category.
In conclusion, There are 3,141 customers in total, of which 2,032 are internet customers and 1,109 are cable customers.
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