All categories

3 years ago

I need help ASAP, please save me.

Mathematics

1 answer:

Sav [38]3 years ago

4 0

Answer:

Angle DCE is a central angle so it's equal to the arc facing it, which is DE, which is given as 116. So angle DCE= 116°

Angle EDF is an angle between a tangent line, DF, and a secant line, DE. So its measure is equal to half of the arc it surrounds, which is arc DE. 116/2= 58°. Angle EDF=58°.

You might be interested in

The denominator of a rational number is greater than its numerator by 5. If 5 is subtracted from the numerator and 4 is added to

nasty-shy [4]

Answer:

7/12.

Step-by-step explanation:

=x/x+5.

x-5/x+5+4=⅛

x-5/x+9=⅛

x-5=⅛(x+9)

x-5=⅛x+1⅛

x-⅛x=1⅛+5

⅞x=49/8

7x=49

x=7

thus the initial fraction is x/x+5= 7/12

A rational number is a fraction

4 0

4 years ago

Last week Rachel power walked 2 3/5 miles per day on each of the 7 days. During the same week, she also jogged 5 3/4 miles per d

Luba_88 [7]

41.2 miles because 3/5=.6 so 2.6 x 7 = 18.2 then for the jogging 3/4 = .75 so 5.75 x 4 = 23 so 23+18.2= 41.2

6 0

3 years ago

Read 2 more answers

The mean value of 8 numbers is 17. Three of these numbers (9, 11, and 20) are discarded.

Viktor [21]

Answer:

19.2

Step-by-step explanation:

You get the mean of a set of numbers by adding them and dividing the sum by how many numbers there are. In this case, you don't know what the individual 8 numbers are, but you can find out what they add up to.

Mean = (sum) / 8

17 = (sum) / 8

17 x 8 = sum

136 = sum

Now take out the numbers 9, 11, 20, which reduces the sum by 40. There are 5 numbers left and they add up to 136 - 40 = 96.

The new mean is 96 / 5 = 19.2

3 0

4 years ago

· The volume of Olivia's rectangular lunchbox is 240 cubic inches. The lunchbox has a height of 3 inches, and its length is 2 in

miskamm [114]

The volume of a cuboid is = length × width × height.

Let the width of Olivia's lunch box be 'x'.

Hence the length of Olivia's lunch box shall be 'x + 2'

Also the height of the box is given as 3 inches.

The volume of the box is 240 in³

Substituting in the formula we get

$x(x+2)(3) =240$

Dividing by 3 on both sides

$x(x+2)=80$

Exapnding we get

$x^2+2x=80$

Subtracting 80 from both sides

$x^2+2x-80=0$

Factoring

$(x+10)(x-8)=0$

We get

x= -10 or x = 8

But x cannot be negative

So x = 8

Hence the width of the box is 8 inches.

7 0

4 years ago

Read 2 more answers

A random sample of size 15 taken from a normally distributed population revealed a sample mean of 75 and a sample variance of 25

GREYUIT [131]

Answer:

The upper limit of a 95% confidence interval for the population mean would equal 83.805.

Step-by-step explanation:

The standard deviation is the square root of the variance. Since the variance is 25, the sample's standard deviation is 5.

We have the sample standard deviation, not the population, so we use the t-distribution to solve this question.

T interval:

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 = 15 - 1 = 14

Now, we have to find a value of T, which is found looking at the t table, with 14 degrees of freedom(y-axis) and a confidence level of 0.95( $t_{95}$ ). So we have T = 1.761

The margin of error is:

M = T*s = 1.761*5 = 8.805.

The upper end of the interval is the sample mean added to M. So it is 75 + 8.805 = 83.805.

The upper limit of a 95% confidence interval for the population mean would equal 83.805.

4 0

4 years ago