SA=4pir^2
78.54km^2=SA
78.54=4pir^2
divide both sides by 4
19.635=pir^2
aprox pi=3.14 so divide both sides by 3.14
6.25318=r^2
sqrt both sides
2.50063=r
round
radius=2.5km
this question is flawed in that it gives the wrong units
answer is the option with 2.5 in it
2nd one
Answer:
see explanation
Step-by-step explanation:
Given D(3, 2 ) → D'(2, 4 )
The x- coordinate of D' is 1 less than D and the y- coordinate of D' is 2 more than D, thus the translation rule is
(x, y ) → (x - 1, y + 2 )
Apply this rule to points O and G
O( 2, - 4 ) → O'(2 - 1, - 4 + 2 ) → O'(1, - 2 )
G(- 1, - 1 ) → G'(- 1 - 1, - 1 + 2 ) → G'(- 2, 1 )
Answer:
The 95% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.2087, 0.2507).
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 zscore that has a pvalue of
.
For this problem, we have that:
Suppose a sample of 1537 tenth graders is drawn. Of the students sampled, 1184 read above the eighth grade level. So 1537 - 1184 = 353 read at or below this level. Then

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 95% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.2087, 0.2507).
Answer:
C) x ÷ 11/12
Step-by-step explanation:
If you divide the total length of string by the length of each piece, you get the number of strings.
total length of string: x
length of each piece: 11/2
We need to divide x by 11/12
Answer: C) x ÷ 11/12