3.9 practice complete your assignment english 111

A bag contains 8 blue marbles, 6 red marbles, and 4 green marbles. What is the probability of se

Digiron [165]

What do you mean by se?

5 0

3 years ago

PLEASE HELP ME ASAP!! I had trouble with this and it is now over due

erica [24]

Answer:

Shira: x = 8

Samuel: m = 0

Step-by-step explanation:

Shira's mistake was that she subtracted 2 from both sides instead of adding to on both sides.

Correct Solving:

2x - 2 = 14

Add 2 to both sides;

2x = 16

Divide both sides by 2;

x = 8

Samuel's mistake was that when he distributed -2 to 8m and 8 he put the wrong sign for -2 * 8.

Correct Solving:

-2(8m + 8) = -16

Distribute;

-16m - 16 = -16

Add 16 to both sides;

-16m = 0

Divide both sides by -16;

m = 0

3 0

3 years ago

A radio is being discounted 30%. If the sale price of the radio is $29.82, what was the original price of the radio?

meriva

Answer: $42.60

Step-by-step explanation:

Original price: p

Discount: 30%

Sale price: 29.82

p x 0.7 = 29.82

p = 29.82/0.7 = 42.60

3 0

2 years ago

(1 point) A cup of coffee at 100 degrees celsius is put into a 30 degree celsius room when t=0. The coffee's temperature, f(t),

Lapatulllka [165]

Answer:your question seems incomplete but if you looking to find the resulting equation to solve for temperature at a particular time you can use this 28t^2

Step-by-step explanation:

F'(t) = 7(0.8)t

Integrating the RHS

Temp= integral of f'(t)= 28t^2

Therefore, T(°c)= 28t^2

3 0

2 years ago

In March 2015, the Public Policy Institute of California (PPIC) surveyed 7525 likely voters living in California. This is the 14

lbvjy [14]

Answer:

We are confident at 99% that the difference between the two proportions is between $0.380 \leq p_{Republicans} -p_{Democrats} \leq 0.420$

Step-by-step explanation:

Part a

Data given and notation

$X_{D}=3266$ represent the number people registered as Democrats

$X_{R}=2137$ represent the number of people registered as Republicans

$n=7525$ sampleselcted

$\hat p_{D}=\frac{3266}{7525}=0.434$ represent the proportion of people registered as Democrats

$\hat p_{R}=\frac{2137}{7525}=0.284$ represent the proportion of people registered as Republicans

The standard error is given by this formula:

$SE=\sqrt{\frac{\hat p_D (1-\hat p_D)}{n_{D}}+\frac{\hat p_R (1-\hat p_R)}{n_{R}}}$

And the standard error estimated given by the problem is 0.008

Part b

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$p_A$ represent the real population proportion of Democrats that approve of the way the California Legislature is handling its job

$\hat p_A =\frac{1894}{3266}=0.580$ represent the estimated proportion of Democrats that approve of the way the California Legislature is handling its job

$n_A=3266$ is the sample size for Democrats

$p_B$ represent the real population proportion of Republicans that approve of the way the California Legislature is handling its job

$\hat p_B =\frac{385}{2137}=0.180$ represent the estimated proportion of Republicans that approve of the way the California Legislature is handling its job

$n_B=2137$ is the sample for Republicans

$z$ represent the critical value for the margin of error

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

The confidence interval for the difference of two proportions would be given by this formula

$(\hat p_A -\hat p_B) \pm z_{\alpha/2} \sqrt{\frac{\hat p_A(1-\hat p_A)}{n_A} +\frac{\hat p_B (1-\hat p_B)}{n_B}}$

For the 90% confidence interval the value of $\alpha=1-0.90=0.1$ and $\alpha/2=0.05$ , with that value we can find the quantile required for the interval in the normal standard distribution.

$z_{\alpha/2}=1.64$

And replacing into the confidence interval formula we got:

$(0.580-0.180) - 1.64 \sqrt{\frac{0.580(1-0.580)}{3266} +\frac{0.180(1-0.180)}{2137}}=0.380$

$(0.580-0.180) + 1.64 \sqrt{\frac{0.580(1-0.580)}{3266} +\frac{0.180(1-0.180)}{2137}}=0.420$

And the 99% confidence interval would be given (0.380;0.420).

We are confident at 99% that the difference between the two proportions is between $0.380 \leq p_{Republicans} -p_{Democrats} \leq 0.420$

5 0

2 years ago