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3 years ago

What is the exact value of cos 225º cos 75°?

Mathematics

2 answers:

love history [14]3 years ago

5 0

Answer:

$-\frac{\sqrt{3} -1}{4}$

Step-by-step explanation:

julsineya [31]3 years ago

3 0

Answer:

√

−

Step-by-step explanation:

i dont kno the other one

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If Angela $98,760 home appreciates 3% a year will she have enough appreciation to try to sell a home for a $15,000 profit in fiv

olasank [31]

Answer:

Yes

Step-by-step explanation:

So, first, in 5 years, the home will have appreciated by 15%. (5 years times 3%). Once you find 15% of 98760, which is 658400, you have to add it on to the original price of the house. At this point, the house costs 757160 dollars. You then subtract the original price of the house from the price of the house 5 years from now. (757160-98760) and you get 658400. As you can tell, 658400>15000. Therefore, the answer is yes.

3 0

3 years ago

Mr Smith bought x number of shirts for the new members of her chorus. The cost for x number of shirts, including $3.99 shipping

fiasKO [112]

We are given that the cost of each shirt = $12.25

It is given that she bought total 'x' shirts, each of cost $12,25.

So, the cost of 'x' shirts is dollars

Also, there is a shipping charge of $3.99

So, the total cost of 'x' shirts is

Since, the shirts cost her total $77.49.

We have the equation,

12.25x + 3.99 = 77.49

4 0

3 years ago

Of 575 broiler chickens purchased from various kinds of food stores in different regions of a country and tested for types of ba

chubhunter [2.5K]

Answer:

a) $0.68 - 2.58 \sqrt{\frac{0.68(1-0.68)}{575}}=0.630$

$0.68 + 2.58 \sqrt{\frac{0.68(1-0.68)}{575}}=0.730$

And the 99% confidence interval would be given (0.630;0.730).

b) We are 99% confident that the true proportion of infected chickens are between 0.63 (63%) and 0.73 (73%)

c) For this case the answer would be No. Since all the required assumptions in order to construct the confidence interval are satisfied, so then the results can be assumed for all the population

Step-by-step explanation:

Previous concepts

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".

$p$ represent the real population proportion of interest

$\hat p =0.68$ represent the estimated proportion

n=575 is the sample size required (variable of interest)

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

The population proportion have the following distribution

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

Part a

The confidence interval would be given by this formula

$\hat p \pm z_{\alpha/2} \sqrt{\frac{\hat p(1-\hat p)}{n}}$

For the 99% confidence interval the value of $\alpha=1-0.99=0.01$ and $\alpha/2=0.005$ , with that value we can find the quantile required for the interval in the normal standard distribution.

$z_{\alpha/2}=2.58$

And replacing into the confidence interval formula we got:

$0.68 - 2.58 \sqrt{\frac{0.68(1-0.68)}{575}}=0.630$

$0.68 + 2.58 \sqrt{\frac{0.68(1-0.68)}{575}}=0.730$

And the 99% confidence interval would be given (0.630;0.730).

Part b

We are 99% confident that the true proportion of infected chickens are between 0.63 (63%) and 0.73 (73%)

Part c

For this case the answer would be No. Since all the required assumptions in order to construct the confidence interval are satisfied, so then the results can be assumed for all the population

4 0

4 years ago

What is the simplified form of the expression?

natali 33 [55]

Answer:

4 sqaure root 24x^3/ 2x

Step-by-step explanation:

See steps below:)

5 0

3 years ago

ON YOUR OWN:

qwelly [4]

Answer:

125 defective jeans

Step-by-step explanation:

We are told that;

During inspections, 5 defective pairs of jeans are found in a shipment of 200 pairs of jeans .

We are supposed to determine the number of defective jeans in a shipment of 5000 pairs, if the trend continues.

Therefore;

5 defective = 200 pairs

What about in 5000 pairs?

Number of defective pairs = (5000 × 5 ) ÷ 200

= 125 defective pairs

Thus, in a shipment of 5000 pairs of jeans there will be 125 defective pairs

6 0

3 years ago