Quest

A radio talk show host with a large audience is interested in the proportion p of adults in his listening area who think the dri

vekshin1

Answer:

The margin of error for a 90% confidence interval is 0.075.

Step-by-step explanation:

We are given that he asks listeners to phone in and vote "yes" if they agree the drinking age should be lowered and "no" if not.

Of the 100 people who phoned in, 70 answered "yes."

Let $\hat p$ = sample proportion of people who say yes

So, $\hat p=\frac{X}{n}$ = $\frac{70}{100}$ = 0.70

where, X = Number of people who say yes = 70

n = Number of people phoned in = 100

Now, Margin of error formula for any confidence interval is given by;

Margin of error = $Z_(_\frac{\alpha}{2}_ ) \times \text{Standard of Error}$

where, $\alpha$ = level of significance = 10%

Standard of error = $\sqrt{\frac{\hat p(1-\hat p)}{n} }$

Also, the critical value of x at 5% ( $\frac{\alpha}{2} =\frac{0.10}{2}$ ) level of significance is 1.645.

SO, Margin of Error = $1.645 \times \sqrt{\frac{\hat p(1-\hat p)}{n} }$

= $1.645 \times \sqrt{\frac{0.70(1-0.70)}{100} }$

= 0.075

Hence, the margin of error for a 90% confidence interval is 0.075.

8 0

3 years ago

-) Which is a valid velocity reading for an object? O 45 m/s O 45 m/s north 23 O O m/s south O 0 m/s ok Save and Exit Next Mark

joja [24]

Answer:

Step-by-step explanation:

0 can't have a direction. It does not move. It has no speed component. Therefore 0 m/s south is not the answer.

45 m/s has no direction stated. It is just a speed, not a velocity.

45 m/s north is a velocity. It has both speed and direction.

4 0

3 years ago

P(A) = 7/20 P(B) = 7/20 P(A or B) = 49/80, P(A and B)= ?

OverLord2011 [107]

Answer:

P(A and B) = 7/80

Step-by-step explanation:

The given values of the probabilities of the different events are;

P(A) = 7/20

P(B) = 7/20

P(A or B) = 49/80

P(A and B) = Required

We have by probability theory for any event;

P(A or B) = P(A) + P(B) - P(A and B)

Therefore;

P(A and B) = P(A) + P(B) - P(A or B)

Plugging in the values gives;

P(A and B) = 7/20 + 7/20 - 49/80 = 7/80

∴ P(A and B) = 7/80

8 0

3 years ago

A box contains a collection of triangular and square tiles. There are 2525 tiles in the box, containing 8484 edges total. How ma

AnnyKZ [126]

Let us consider the number of edges = x
we know that a triangle will have 3 edges and a square will have 4 edges. Using this details we can form an equation.
3x + 4x = 8484
7x = 8484
x = 8484/7
= 1212
Then
Number of square tiles = 1212/4
= 303
So there are 303 square tiles in the box. I hope the procedure is clear enough for your understanding. You can always use this method for solving similar problems.

5 0

3 years ago

What is 57,020,000 expressed in scientific notation

densk [106]

Answer:

$57,020,000 = 5.702\cdot10^7$

8 0

3 years ago