A. Suppose a hospital would like to estimate the proportion of patients who feel that physicians who care for them always communicated effectively when discussing their medical care. A pilot sample of 40 patients found that 24 reported that their physician communicated effectively. Determine the additional number of patients that need to be sampled to construct a 90​% confidence interval with a margin of error equal to 8​% to estimate this proportion. The additional number of patients that need to be sampled is __? (Round up to the nearest​ integer.)

B.

A tire manufacturer would like to estimate the average tire life of its new​ all-season light truck tire in terms of how many miles it lasts. Determine the sample size needed to construct a 98​% confidence interval with a margin of error equal to 2,700 miles. Assume the standard deviation for the tire life of this particular brand is 7,000 miles. The sample size needed is _? ​(Round up to the nearest​ integer.)

C.

A certain region would like to estimate the proportion of voters who intend to participate in upcoming elections. A pilot sample of 50 voters found that 28 of them intended to vote in the election. Determine the additional number of voters that need to be sampled to construct a 92​% interval with a margin of error equal to 0.06 to estimate the proportion. The region should sample __? additional voters. ​(Round up to the nearest​ integer.)

D.

Determine the sample size n needed to construct a 95​% confidence interval to estimate the population proportion for the following sample proportions when the margin of error equals 5​%.

I. p=0.20

II. p=0.30

III. p=0.40

a.   we have two

lines:   y = 4-x   and  

y = 8-x^-1

given two simultaneous equations that are both to be

true, then the solution is the points where the lines cross. the intersection is

where the two equations are equal. therefore the solution that works for both

equations is when

4-x = 8-x^-1

this is where the two lines will cross and that is the

common point that satisfies both equations.

b.   4-x = 8-x^-1

  x           4-x       8-x^-1

-3           7        

8.33

-2           6         8.5

-1           5         9

  0           4        

-

  1           3        

7

  2           2        

7.5

  3           1         7.67

the table shows that none of the x values from -3 to 3 is

the solution because in no case does

4-x = 8-x^-1

to find the solution we need to rearrange the equation to

find for x:

4-x = 8-x^-1

multiply both sides with x:

4x-x^2 = 8x-1

x^2+4x-1=0

x= -4.236, 0.236

therefore there are two points that satisfies the

equation.

find y:  

x=-4.236

y = 4-x   = 4 – (-4.236)

= 8.236

y = 8-x^-1 =   .236)^-1

= 8.236

x=0.236

  y = 4-x   = 4 – (0.236) = 3.764

y = 8-x^-1 =   8-(0.236)^-1

= 3.764

thus the two lines cross at 2 points:

(-4.236, 8.236) & (0.236, 3.764)

c.   to solve

graphically the equation 4-x = 8-x^-1

we would graph both lines: y = 4-x   and   y

= 8-x^-1

the point on the graph where the lines cross is the

solution to the system of equations.

just graph the points on part b on a cartesian coordinate

system and extend the two lines.   the

solution is, as stated, the point where the two lines cross on the graph.

step-by-step explanation:

mark brainliest!

this is a good question! i’ll do some research and what i find, i’ll contact you asap when i have something! ✊