Answer:
15000
Step-by-step explanation:
Given that a professor wants to know how undergraduate students at X University feel about food services on campus, in general. She obtains a list of email addresses of all 15,000 registered undergraduates from the registrar’s office and mails a questionnaire to 300 students selected at random.
Only 150 questionnaires are returned.
So the sample size changed to 150. But population is the number of registered undergraduates which do not change.
Population size = 15000
Answer:
21.72
Step-by-step explanation:
0.07 x 20.30
Solution:
Using Substitution Method:
-4x+7y=-5 (Equation 1)
x-3y=-5 (Equation 2)
get the value of x from Equation 2
x=3y-5 (Equation 3)
Put the value of x from Equation 3 in Equation 1
-4(3y-5)+7y=-5
-4(3y)+20+7y=-5
-12y+7y=-5-20
-5y=-25
Negative sign on both sides cancels each other
y=25/5
y=5
Putting value of y in equation 3
x=3(5)-5
x=15-5
x=10
Therefore, [x,y]=[10,5]
Using Elimination Method
-4x+7y=-5 (Equation 1)
x-3y=-5 (Equation 2)
Multiply equation 2 with -4 in order to eliminate the x term
-4(x-3y)=-5*4
-4x+12y=20 (Equation 3)
Adding Equation 1 and 3
-4x+7y=-5
-4x+12y=20
+ - = - (Change Of Sign with x and y terms)
-----------------
0x-5y = -25
-5y=-25
y=5
Substituting y’s value is Equation 1
-4x+7(5)=-5
-4x+35=-5
-4x=-40
Cancellation of negative sign on both sides
x=40/4
x=10
[x,y]=[10,5]
