5 x 7824984262984 ÷ 76

A survey reported in Time magazine included the question ‘‘Do you favor a federal law requiring a day waiting period to purchase

il63 [147K]

Answer:

The 90% confidence interval for the difference between proportions is (-0.260, -0.165).

Step-by-step explanation:

The question is incomplete. The complete question is:

"A survey reported in Time magazine included the question ‘‘Do you favor a federal law requiring a 15 day waiting period to purchase a gun?” Results from a random sample of US citizens showed that 318 of the 520 men who were surveyed supported this proposed law while 379 of the 460 women sampled said ‘‘yes”. Use this information to find a 90% confidence interval for the difference in the two proportions, pm - pw. Subscript pm is the proportion of men who support the proposed law and pw is the proportion of women who support the proposed law. (Round answers to 3 decimal places.)"

We want to calculate the bounds of a 90% confidence interval.

For a 90% CI, the critical value for z is z=1.645.

The sample of men, of size nm=-0.26 has a proportion of pm=0.612.

$p_m=X_m/n_m=318/520=0.612$

The sample 2, of size nw= has a proportion of pw=0.824.

$p_w=X_w/n_w=379/460=0.824$

The difference between proportions is (pm-pw)=-0.212.

$p_d=p_m-p_w=0.612-0.824=-0.212$

The pooled proportion, needed to calculate the standard error, is:

$p=\dfrac{X_m+X_w}{n_m+n_w}=\dfrac{318+379}{520+460}=\dfrac{697}{980}=0.711$

The estimated standard error of the difference between means is computed using the formula:

$s_{pm-pw}=\sqrt{\dfrac{p(1-p)}{n_m}+\dfrac{p(1-p)}{n_w}}=\sqrt{\dfrac{0.711*0.289}{520}+\dfrac{0.711*0.289}{460}}\\\\\\s_{pm-pw}=\sqrt{0.00039+0.00045}=\sqrt{0.001}=0.029$

Then, the margin of error is:

$MOE=z \cdot s_{pm-pw}=1.645\cdot 0.029=0.0477$

Then, the lower and upper bounds of the confidence interval are:

$LL=(p_1-p_2)-z\cdot s_{p1-p2} = -0.212-0.0477=-0.260\\\\UL=(p_1-p_2)+z\cdot s_{p1-p2}= -0.212+0.0477=-0.165$

The 90% confidence interval for the difference between proportions is (-0.260, -0.165).

6 0

3 years ago

The volume of a sphere is 972(pi)ft3.

pav-90 [236]

Here are some simple equations that can be a life saver with this stuff :

vol of a sphere =

$v = \frac{3}{4} \pi \: {r}^{3}$

Circumference =

$2 \times \pi \times r$

sorry this might not be very helpful. I haven't don't this since last year. You basically have to work backwards. so plug in 972 for V and then do (3/4)×3.14.

then take the answer u got for ^^ and divide it by 2? not sure.

7 0

3 years ago

6 in 24 in I don’t get this at all and I have trouble with math

nekit [7.7K]

What’s the full question?

6 0

3 years ago

The sum of 3 consecutive numbers are 24. What are the numbers? Please explain.

victus00 [196]

Consecutive numbers mean in order from smallest to largest, therefore, 7, 8, 9, would be the answer. 7+8+9=24.

4 0

4 years ago

PLEASE HELP me I am struggling.

mihalych1998 [28]

Answer:

ab - b^2

Step-by-step explanation:

The area of the large rectangle is

A = a*b

The area of the unshaded region is

A = b*b

The area of the shaded region is the large rectangle minus the unshaded region

ab - b*b

or

ab - b^2

3 0

3 years ago