Please help me out............

Find the appropriate rejection regions for the large-sample test statistic z in these cases. (Round your answers to two decimal

Usimov [2.4K]

Answer:

a) We have that the significance is given by $\alpha =0.01$ and we know that we have a right tailed test.

So for this case we need to look in the normal standard dsitribution a critical value that accumulates 1% of the area on the right and 99% of the area on the left. This value can be founded with the following excel code:

"=NORM.INV(1-0.01,0,1)"

And we got for this case $z_{crit}=2.33$

So then the rejection region would be $z>2.33$

b) We have that the significance is given by $\alpha =0.05$ , $\alpha/2 =0.025$ and we know that we have a two tailed test.

So for this case we need to look in the normal standard dsitribution a critical value that accumulates 2.5% of the area on the right and 97.5% of the area on the left. This value can be founded with the following excel code:

"=NORM.INV(1-0.025,0,1)"

And we got for this case $z_{crit}=\pm 1.96$

So then the rejection region would be $z>1.96 \cup z$

Step-by-step explanation:

Part a

We have that the significance is given by $\alpha =0.01$ and we know that we have a right tailed test.

So for this case we need to look in the normal standard dsitribution a critical value that accumulates 1% of the area on the right and 99% of the area on the left. This value can be founded with the following excel code:

"=NORM.INV(1-0.01,0,1)"

And we got for this case $z_{crit}=2.33$

So then the rejection region would be $z>2.33$

Part b

We have that the significance is given by $\alpha =0.05$ , $\alpha/2 =0.025$ and we know that we have a two tailed test.

So for this case we need to look in the normal standard dsitribution a critical value that accumulates 2.5% of the area on the right and 97.5% of the area on the left. This value can be founded with the following excel code:

"=NORM.INV(1-0.025,0,1)"

And we got for this case $z_{crit}=\pm 1.96$

So then the rejection region would be $z>1.96 \cup z$

7 0

3 years ago

Which of the following are solutions to the equation below 3x^2+27x+54=0

VikaD [51]

Answer:x=6

Step-by-step explanation:Step-1 : Multiply the coefficient of the first term by the constant 1 • 18 = 18

Step-2 : Find two factors of 18 whose sum equals the coefficient of the middle term, which is -9 .

-18 + -1 = -19

-9 + -2 = -11

-6 + -3 = -9 That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -6 and -3

x2 - 6x - 3x - 18

Step-4 : Add up the first 2 terms, pulling out like factors :

x • (x-6)

Add up the last 2 terms, pulling out common factors :

3 • (x-6)

Step-5 : Add up the four terms of step 4 :

(x-3) • (x-6)

Which is the desired factorization

7 0

3 years ago

Read 2 more answers

A cafe offers senior citizens a 15% discount off its regular price of $8.95 for the dinner buffet.

jonny [76]

a) 75 percent of the regular price is the price for senior citizens.

b) $6.712 is the price for senior citizens.

<u>Step-by-step explanation</u>:

The regular price is the 100% = $8.95
The offer price for senior citizen = 15% discount from 100%

∴ Percent of the regular price for senior citizens = 100% - 15% = 75%

The price for the senior citizens = 75% of $8.95

⇒ (75/100) $\times$ 8.95

⇒ 0.75 $\times$ 8.95

⇒ 6.712 dollars.

∴ The price for senior citizens = $6.712

7 0

3 years ago

The height of a triangle is 7 ft more than its base. if the area of the triangle is 30 ft^ what is the lentgh of the base

Dmitriy789 [7]

Since the area of a triangle is in the form
area=0.5(base)(height)
height=base+7
let base=x
area=0.5(x)(7+x)
30=3.5x+0.5x^2
multiply the equation by 2
60=7x+x^2
subtract 60 from both sides
x^2+7x-60=0
(x-5)(x+12)=0
thus x=5 or x=-12 since we are only considering positive answers
x=-12 is rejected
so base=5 and height=5+7=12

6 0

3 years ago

A grocery store recieves a 180-pound crate containing six 10-pound bags of potatos and an unknown number of 5-pound bags of pota

Diano4ka-milaya [45]

Answer:

$60+5x = 180$

Step-by-step explanation:

Let the number of bags of potatoes be x.

We have been given that a grocery store receives a 180-pound crate containing six 10-pound bags of potatoes and an unknown number of 5-pound bags of potatoes.

The weight of 6 potato bags of 10 pound each will be $6\times 10=60$ pounds.

We can write an equation for the number of bags of potatoes by equating the weight of six 10-pound bags of potatoes and x 5-pound bags of potatoes with 180 pounds.

$6*10+5x = 180$

$60+5x = 180$

Therefore, the equation that represents the number of bags of potatoes in the crate is $60+5x = 180$ .

5 0

2 years ago