An article which cost money 150 was sold at a loss of 5%.what was the selling price?

Construct a 99% confidence interval for the population mean, mu. Assume the population has a normal distribution. A group of 1

Zarrin [17]

Answer:

99% confidence interval for the population mean is [19.891 , 24.909].

Step-by-step explanation:

We are given that a group of 19 randomly selected students has a mean age of 22.4 years with a standard deviation of 3.8 years.

Assuming the population has a normal distribution.

Firstly, the pivotal quantity for 99% confidence interval for the population mean is given by;

P.Q. = $\frac{\bar X - \mu}{\frac{s}{\sqrt{n} } }$ ~ $t_n_-_1$

where, $\bar X$ = sample mean age of selected students = 22.4 years

s = sample standard deviation = 3.8 years

n = sample of students = 19

$\mu$ = population mean

<em>Here for constructing 99% confidence interval we have used t statistics because we don't know about population standard deviation.</em>

So, 99% confidence interval for the population mean, $\mu$ is ;

P(-2.878 < $t_1_8$ < 2.878) = 0.99 {As the critical value of t at 18 degree of

freedom are -2.878 & 2.878 with P = 0.5%}

P(-2.878 < $\frac{\bar X - \mu}{\frac{s}{\sqrt{n} } }$ < 2.878) = 0.99

P( $-2.878 \times {\frac{s}{\sqrt{n} } }$ < ${\bar X - \mu}$ < $2.878 \times {\frac{s}{\sqrt{n} } }$ ) = 0.99

P( $\bar X -2.878 \times {\frac{s}{\sqrt{n} }$ < $\mu$ < $\bar X +2.878 \times {\frac{s}{\sqrt{n} }$ ) = 0.99

<u>99% confidence interval for</u> $\mu$ = [ $\bar X -2.878 \times {\frac{s}{\sqrt{n} }$ , $\bar X +2.878 \times {\frac{s}{\sqrt{n} }$ ]

= [ $22.4 -2.878 \times {\frac{3.8}{\sqrt{19} }$ , $22.4 +2.878 \times {\frac{3.8}{\sqrt{19} }$ ]

= [19.891 , 24.909]

Therefore, 99% confidence interval for the population mean is [19.891 , 24.909].

6 0

3 years ago

Olivia is making scarves each scarf will have 5 rectangles and 2/5 of the rectangles will be purple how many purple rectangles d

Tomtit [17]

Answer:

Out of every 5 rectangles 2 shall be purple.

3 scarves have 3 times 5 rectangles.

Thus they shall be 3 times 2 that are purple.

Step-by-step explanation:

8 0

3 years ago

Find the midpoint given the endpoints (4,-10) (22,-4) Please do not use space when

Elza [17]

Answer: (13,-7)

Step-by-step explanation:

By using the formula $(x_{m},y_{m}) =(\frac{x_{1}+x_{2} }{2},\frac{y_{1}+y_{2} }{2} )$

$(x_{m},y_{m})\\$ is the coordinates of the midpoint.

For finding the midpoint X variable do:

$(\frac{4+22}{2})=13$

For finding the midpoint Y variable do:

$\frac{-10+(-4)}{2} = -7$ (you can either keep the parenthesis or take them out. Either way, the answer is the same.

Considering coordinate numbers follow the format: (x,y), you'll simply just substitute the numbers found above into their respective places.

x: 13

y: -7

(13,-7).

6 0

2 years ago

Kaylee drove her scooter at an average speed of 15 miles per hour. Sophia drove her scooter at an average speed of 10 miles per

maksim [4K]

Answer:

Kaylee drove her scooter for 2h and Sophia drove her scooter for 3h.

Step-by-step explanation:

From the graph shown below, we can see that the intersection point is (2,3). When using the graphing method to solve a system of equations, the intersection point is the answer. In this case, x = 2 and y = 3.

Thus, Kaylee drove her scooter for 2h and Sophia drove her scooter for 3h.

5 0

3 years ago

Mark earns $300 per month plus an additional 2% on all of his sales. Last month he sold $59,000. What was Mark's income for the

KatRina [158]

Answer:

59,000 times 0.02= $1,180 commission plus $300 = $1480

In order to get your answer you have to change the percent into a decimal and it’s commission so you have to add.

7 0

2 years ago