Answer:
Total number of points in the test = 100
Total number of items in the test = 40
Let number of items of 2 points be x and number of items of 3 points be y.
Now, using the given information the situation can be represented by using the following equations :
⇒ x + y = 40 .........(1)
⇒ 2x + 3y = 100 .........(2)
The matrix equation is :
By solving the equation (1) and equation (2), we get :
Solution : x = 20 and y = 20
Answer:
192.92 ft^3
Step-by-step explanation:
volume of a cone = πr²h
π = 3.14
r = radius ]
h = height
the base of a cone is in the shape of a circle. thus, the circumference of the base is equal to the circumference of a circle
circumference of a circle= 2πr
30.144 = 2 x 3.14 x r
r = 30.144 / 6.28
r = 4.8
Volume = 1/3 x 3.14 x 4.8² x 8 = 192.92 ft^3
Answer:
A sample of 997 is needed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of , and a confidence level of
, we have the following confidence interval of proportions.
In which
z is the z-score that has a p-value of .
The margin of error is of:
A previous study indicates that the proportion of left-handed golfers is 8%.
This means that
98% confidence level
So , z is the value of Z that has a p-value of
, so
.
How large a sample is needed in order to be 98% confident that the sample proportion will not differ from the true proportion by more than 2%?
This is n for which M = 0.02. So
Rounding up:
A sample of 997 is needed.