Find the value of x in the triangle shown below.

choli [55]

This is 25 divided by 2000 times 100

6 0

3 years ago

In a survey, 24 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped

erica [24]

Answer:

The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 24 - 1 = 23

98% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 23 degrees of freedom(y-axis) and a confidence level of $1 - \frac{1 - 0.98}{2} = 0.99$ . So we have T = 2.5

The margin of error is:

$M = T\frac{s}{\sqrt{n}} = 2.5\frac{2}{\sqrt{24}} = 1.02$

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 42 - 1.02 = $40.98.

The upper end of the interval is the sample mean added to M. So it is 42 + 1.02 = $43.02.

The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.

7 0

3 years ago

What is the system of inequalities associated with the following graph?

GarryVolchara [31]

Answer: C

Step-by-step explanation:

$y=-2$ is dotted and shaded below, so it represents $y < -2$ .

Also, $x+y=1$ is shaded above, so it represents $x+y < 1$ .

3 0

2 years ago

Find the equation of the circle with center (4,5) which passes through the y-intercept of the line 5x-2y+6=0

Elena-2011 [213]

Answer:

(x-4)^2 + (y-5)^2 = 20

Step-by-step explanation:

Rearrange the line equation of 5x - 2y + 6 = 0

So y = 5/2x +3

The y-intercept of the line equation is 3 as when x=0, y=3.

We know the Circle has the formula $(x-4)^2 + (y-5)^2 = ?^2$ from the question but with the intercept, we can find the entire equation as the y-intercept is (0,3) so we can substitute it into the equation to find the full equations so: