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2 years ago

Help! Will give brainliest! (Whatever it’s called ) Thank you!! Find the surface area! :)

Mathematics

2 answers:

ladessa [460]2 years ago

8 0

Answer:

A=777.54

Step-by-step explanation:

What you do is use the formula which is

a=2pirh+2pir^2.

The radius is half the diameter and the diameter is 15 so you take 15 and divide it by 2 to get 7.5.

The height is 9 m.

A=2(3.14)(7.5)(9)+2(3.14)(7.5)^2=777.54 m.

Sever21 [200]2 years ago

7 0

Answer:

777.15 m^2

Step-by-step explanation:

To find the surface area of a cylinder

SA = 2 pi r h + 2 pi r^2

The area of the sides Plus the area of the top and bottom

We know the diameter is 15 so the radius is 1/2 (15) = 7.5

SA = 2 * pi * (7.5) * 9 + 2 * pi * (7.5)^2

= 135pi + 112.5pi

247.5 pi

Approximating pi with 3.14

247.5 (3.14)

777.15 m^2

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2. What is the quotient of -18 divided by (- 1/6)?<br> A -108<br> С 3<br> B -3<br> D 108

vivado [14]

Positive 3 is the answer

6 0

3 years ago

James is kayaking. He can row 3 mph in still water. If he can travel 6 miles downstream in the same amount of time that he can t

nekit [7.7K]

Answer: the speed of the current is 0.6 mph

Step-by-step explanation:

Let x represent the speed of the current.

James is kayaking. He can row 3 mph in still water. If he can travel 6 miles downstream. Assuming he went with the current, it means that his total speed while travelling downstream is (3 + x)

Time = distance/speed

Time taken to travel downstream is

6/(3 + x)

In the same amount of time, he can travel 4 miles upstream. Assuming he went against the current, it means that his total speed while travelling downstream is (3 - x). Time taken to travel upstream is

4/(3 - x)

Since the time is the same, then

6/(3 + x) = 4/(3 - x)

Cross multiplying, it becomes

6(3 - x) = 4(3 + x)

18 - 6x = 12 + 4x

4x + 6x = 18 - 12

10x = 6

x = 6/10

x = 0.6 mph

4 0

3 years ago

Scores on a college entrance examination are normally distributed with a mean of 500 and a standard deviation of 100. What perce

Alla [95]

Answer:

The percentage is $P(350 < X 650 ) = 86.6\%$

Step-by-step explanation:

From the question we are told that

The population mean is $\mu = 500$

The standard deviation is $\sigma = 100$

The percent of people who write this exam obtain scores between 350 and 650

$P(350 < X 650 ) = P(\frac{ 350 - 500}{ 100}$

Generally

$\frac{X - \mu }{\sigma } = Z (The \ standardized \ value \ of \ X )$

$P(350 < X 650 ) = P(\frac{ 350 - 500}{ 100}$

$P(350 < X 650 ) = P(-1.5$

$P(350 < X 650 ) = P(Z < 1.5) - P(Z < -1.5)$

From the z-table $P(Z < -1.5 ) = 0.066807$

and $P(Z < 1.5 ) = 0.93319$

=> $P(350 < X 650 ) = 0.93319 - 0.066807$

=> $P(350 < X 650 ) = 0.866$

Therefore the percentage is $P(350 < X 650 ) = 86.6\%$

3 0

3 years ago

If you walk 5/12 in 1/2 hour how dar will you walk in 1 hour

riadik2000 [5.3K]

Answer:

10/12 or 5/6

Step-by-step explanation:

1/2 + 1/2 = 1

5/12 + 5/12 = 10/12 or 5/6

3 0

2 years ago

Read 2 more answers

According to the US Bureau of labor statistics, 7% of US female workers between 16 and 24 years old are paid at the minimum wage

vladimir1956 [14]

Answer:

The Null Hypothesis is $H_o:k_o = 0.07$

The alternative hypothesis is $H_a :k_o \ne 0.07$

Decision rule

If the test staistics is greater than the critical value of significance level then $H_o$ is accepted else $H_o$ is rejected

With the above in mind

The critical value of the significance level which is obtained from the table is

$t_{0.05} = 1.645$

Now since the critical value of significance level is greater than the test staistics then the null hypothesis will be rejected

Conclusion

The information is not enough to back the claim that state differs from the nation

Step-by-step explanation:

From the question we are told that

The percentage of US female workers paid at the minimum wage or less is $k_o =$ 7% = 0.07

The sample size is $n = 500$

The number paid minimum wage or less is x = 42

The significance level is $\alpha =$ 5% = 0.05

Now the probability of getting a US female workers paid at the minimum wage or less is mathematically represented as

$\= k = \frac{x}{n}$

substituting value

$\= k = \frac{42}{500}$

$\= k = 0.084$

The Null Hypothesis is $H_o:k_o = 0.07$

The alternative hypothesis is $H_a :k_o \ne 0.07$

Generally the test statistics is mathematically evaluated as

$z = \frac{\= k - k_o}{\sqrt{\frac{k_o(1-k_o)}{n} } }$

substituting value

$z = \frac{0.084 - 0.07}{\sqrt{\frac{0.07 (1-0.07)}{500} } }$

$z = 1.23$

Now the Decision rule is stated as

If the test staistics is greater than the critical value of significance level then $H_o$ is accepted else $H_o$ is rejected

With the above in mind

The critical value of the significance level which is obtained from the table is

$t_{0.05} = 1.645$

Now since the critical value of significance level is greater than the test staistics then the null hypothesis will be rejected

So the conclusion will be

The information is not enough to back the claim that state differs from the nation

4 0

3 years ago