Please help me the answers with an x next to them are wrong, and it’s not the other way around please help!!

mylen [45]

Answer:

103, 776

Step-by-step explanation:

There are 48 possibilities, and you are picking 3.

Now, the order does matter (aka, if the same 3 athletes won but got different places, we would still consider it to be a separate possibility)

(this is considered "without repetitions")

the number of permutations (arrangement combinations where the order does matter) without repetitions formula:

Number of permutations

without repetitions = nPr

= $\frac{n!}{(n-r)!}$

(

[the P is for combinations [where the order does matter, if the order didn't matter then it would be C, and it would be a different formula.]

n is the total number of objects.

r is the number of objects selected]

(a repetition would be like two versions of the same person competing, which doesn't make sense)

{the ! means factorial:

5! = 5 x 4 x 3 x 2 x 1}

{for example, if there are 5 people to give a presentation, and they can go in any order [but cannot repeat their presentation], so they all must fill 5 slots}

{for the first slot there are 5 choices, the second slot there are 4 choices...}

)

So, if we follow this formula:

$\frac{n!}{(n-r)!}$

n: 48

r: 3

$\frac{48!}{(48-3)!}$

= $\frac{48!}{45!}$

= $\frac{48 * 47*46*45!}{45!}$

(the 45! cancel out)

= 48 * 47 * 46

= 103, 776

(or, without the formula:

for the first choice (lets say of gold), there are 48 options

for the second choice (lets say silver), there are 47 options left to choose from

for the third choice (lets say bronze), there are 46 options left to choose from

)

3 0

2 years ago

The equation of line / is y=3x/a +5, where a is a positive constant. If the value of a in this equation is doubled, then the res

Anettt [7]

The resulting equation will represent a line whose slope is 1/2 times the slope of the line

<h3>How to determine the slope of the new line?</h3>

The equation of the line is given as:

y = 3x/a + 5

The constant a is a positive constant.

So, when the value of a in the equation is doubled, we have:

y = 3x/2a + 5

A linear equation is represented as

y = mx + b

Where m represents the slope.

So, we have:

m1 = 3/a

m2 = 3/2a

Substitute m1 = 3/a in m2 = 3/2a

m2 = 1/2 * m1

Hence, the resulting equation will represent a line whose slope is 1/2 times the slope of the line

Read more about linear equation at:

brainly.com/question/14323743

#SPJ1

6 0

2 years ago

Describe and correct the error the student made when writing the equation of the line that passes through (-8,5)

pshichka [43]

Option D (The student should have used as the slope of the perpendicular line.) is correct.

Step-by-step explanation:

We need to identify the error that the student made in finding equation of the line that passes through (-8,5) and is perpendicular to y = 4x + 2

The slope of the required line would me -1/m because both lines are perpendicular.

So, slope of new line will be: -1/4

because the equation of slope-intercept form is: $y=mx+b$ where m is the slope

Now, for finding equation the student used point slope form i.e $y-y_1=m(x-x_1)$

where y_1 and x_1 are the points and m is the slope.

Putting values:

x_1=-8, y_1=5 and m=-1/4

$y-5=-\frac{1}{4}(x-(-8))\\y-5=-\frac{1}{4}(x+8)\\y-5=-\frac{1x}{4}-2\\y=-\frac{1x}{4}-2+5\\y=-\frac{1x}{4}+3$

This is the correct solution.

The student made error by using the wrong slope he used 2 instead of -1/4

in the step $y-5 = 2(x-(-8))$

So, Option D (The student should have used as the slope of the perpendicular line.) is correct.

Keywords: Equation of line using Slope

Learn more about Equation of line using Slope at:

#learnwithBrainly

3 0

3 years ago

Read 2 more answers

In order to estimate the average time spent on the computer terminals per student at a local university, data were collected fro

VladimirAG [237]

Answer:

Margin of error for a 95% of confidence intervals is 0.261

Step-by-step explanation:

Step1:-

Sample n = 81 business students over a one-week period.

Given the population standard deviation is 1.2 hours

Confidence level of significance = 0.95

Zₐ = 1.96

Margin of error (M.E) = $\frac{Z_{\alpha }S.D }{\sqrt{n} }$

Given n=81 , σ =1.2 and Zₐ = 1.96

Step2:-

 $Margin of error (M.E) = \frac{Z_{\alpha }S.D }{\sqrt{n} }$ 

 $Margin of error (M.E) = \frac{1.96(1.2) }{\sqrt{81} }$ 

On calculating , we get

Margin of error = 0.261

Conclusion:-

Margin of error for a 95% of confidence intervals is 0.261

4 0

4 years ago

If Train A is moving 66 mph and is 456 miles from the station while Train B is moving 72 mph and is 502 miles away, which train

Len [333]

Answer: train A arrives first

Step-by-step explanation:

7 0

3 years ago