n
2. (a) If ^nP2= 20, find the value of n.
2​

Answers

Answer 1

Answer:

[tex]n = 5[/tex]

Step-by-step explanation:

Given

[tex]^nP_2 = 20[/tex]

Required

Find n

To do this, we apply permutation formula.

[tex]^nP_r = \frac{n!}{(n-r)!}[/tex]

So, we have:

[tex]\frac{n!}{(n-2)!} = 20[/tex]

Expand the numerator

[tex]\frac{n(n-1)(n-2)!}{(n-2)!} = 20[/tex]

Divide by (n-2)!

[tex]n(n-1)= 20[/tex]

Expand

[tex]n^2 - n = 20[/tex]

[tex]n^2 - n - 20 = 0[/tex]

Expand

[tex]n^2 +4n -5n - 20 = 0[/tex]

Factorize

[tex]n(n+4)-5(n+4)= 0[/tex]

[tex](n-5)(n+4) = 0[/tex]

[tex]n - 5 = 0[/tex] or [tex]n + 4 = 0[/tex]

[tex]n = 5[/tex] or [tex]n = -4[/tex]

Since n cannot be negative, then:

[tex]n = 5[/tex]


Related Questions

Using the graph below, what is f(5)?

Answers

F(5) would be the y value of where the line is when it is at x 5

The line crosses at -6.5

F(5) = -6.5

d.
a.
b.
12
8
Which triangles are similar?
8
3
25
(25
25
25
6
6
16
Ос
od
Оа
O
b

Answers

Answer:

C and d

Step-by-step explanation:

C and d are similar triangles. I think that’s what you mean. I just did the test

what is the unit rate for 350 miles in 7 hours

Answers

Answer:

50 miles per hour

Step-by-step explanation:

Just divide 350 by 7

50 miles- divide 350 by 7 to find
the unit rate

Find the average rage of change of each of the following functions over the interval 1 < × < 5.

Answers

not sure maybe 45 or 10

How many ounces are in 13 pounds

Answers

Answer:

There are 208 ounces in 13 pounds :)

Answer:

208 oz

Step-by-step explanation:

1 lb = 16 oz

Where you see 1 lb, substitute it with 16 oz.

13 lb = 13 * 1 lb = 13 * 16 oz = 208 oz

What is the value of the Expression
H-20 when h=60?

A:30
B:40
C:80
D:120

Answers

Answer:

BBBBBBBB

Step-by-step explanation:

Answer:

40

Step-by-step explanation:

Subtract 60-20 you'll get the answer

Tim has a friend, John, across the world he wants to transfer 1000$ to. However, his bank charges a 0.3% fee on the value of every transfer. Tim wants John to receive 1000$ after the fees, which means that Tim needs to send more than 1000$ for him to cover the fees the bank charges. How much should Tim send so that John receives 1000$ in his account after fees?

Answers

Answer:

1003

Step-by-step explanation:

as Tom has to sent amount of money =

1000 (amount of money that john needs) + 0.3%*1000 (fee) = 1000+ 3 = 1003

Luke has a bag of hay that weighs 14.7 ounces. He wants to divide the hay into 3 equal piles. Luke solves the equation 3w = 14.7. What is the weight of each pile of hay?

Answers

Answer:

4.9 oz.

Step-by-step explanation:

You divide 14.7 by 3 to get 4.9 oz. Hope this helps.

A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z.

Answers

Answer:

Width  2in

height 3in

length 4in

Step-by-step explanation:

If he want the length to be four he has to take 2 sqares off at the end to be left with his height as 3 so vertical from top to bottom and width (the two sqaures at the end of the photo to the left) would be 2.    :)

Width of box=2in

Height of box=3in

Length of box=6in

Volume=2(3)(6)=36in³

Now

length of the box is 4in

Product of width and height=36/4=9in²

They must be of 3×3 in or 4.5×2 in

Help please if u
You don’t know it please don’t answer.

Answers

i believe the answers are the following:

5. x = ±3.4641i

6. x = ±7

hope this helped! please mark brainliest if you get the chance :)

Explain how to solve the problem y = (xz)/ x for y when x = 3 and z = 2.

Answers

Answer:

y=6

standard form

consider the function f(x)=2x-3
A) Evaluate f

Answers

Answer:

The Answer is a(x)+3x-10

Step-by-step explanation:

Answer:

please give f(?) like f of what? if you give that i will be able to help you more

Step-by-step explanation:

Please help, at it with these graphs again, thanks in advance.

One car is increasing its speed at a steady rate, while another car is decreasing its speed at a steady rate. The speed (y) over time (x) for the cars is represented by the following system of equations.

(picture of graph)

After _[blank A]_ minutes, both cars were traveling at a speed of _[blank B]_ miles per hour.

Enter your answer as the values that correctly fill in the blanks in the previous sentence, in the correct order, and separated by a comma, like this: 42, 53

Answers

Answer:

5, 45

Step-by-step explanation:

Save me Lol I suck at math :D

Answers

Answer:

5/w-v

Step-by-step explanatio

A student is able to finish 2 homework problems per hour. If they have already completed 4 problems, how many hours will it take for them to finish an assignment which has 18 problems total? Give your answer to two decimal places.

Answers

Answer:

Step-by-step explanation:

4+2t=18

2t=14

t=7 hours

Answer:

7.00 hours

Step-by-step explanation:

They already did 4 problems and need to do 18 problems in total.

18 - 4 = 14 problems

2 problems/ per hour

14 problems/ 7 hours

It will take them 7 hours to finish. Since you said "Give your answer to two decimal places." You could write it as 7.00 hours.

PLZ HELP!! I NEED QUICKLY!!
Choose 5 ordered pairs whose first and second coordinate are equal. Plot these points and connect them. What kind of figure do you get? In what quadrants does the figure lie?

Answers

Answer:

no worries about the other day and I had literally forgotten about the other night and was just so I could tell me how I felt and I had a flat rate that you and I had a

The figure of y = x will be a straight line with slope 1 and they ;lie in the first quadrant and the third quadrant.

What is Linear Function?

A linear function can be defined as the function whose graph is a straight line. It can also be defined as the function with one or more variables but does not have exponents to the variables or the exponent of the variable is 1.

We have to choose 5 ordered pairs first whose first and second coordinate are equal.

Let the coordinates be (-4, -4), (-2, -2), (0, 0), (2, 2) and (4, 4).

The ordered pairs are of the form (x, x), that both the coordinates have same value.

So we get a linear function y = x

The graph of a linear function will be a straight line.

Since y = x, the graph will be a straight line which tends to the positive direction and the slope of the line = 1.

That is , the angle that the line making with the X axis is 45°.

And the figure lies on first and third quadrant.

Hence the figure of y = x would be a straight line with slope 1.

To learn more about Linear Functions, click :

https://brainly.com/question/21107621

#SPJ2

As part of a survey, 300 girls were asked to name their favorite sport. The results shows that 12 of
the girls named bowling as their favorite sport. What percentage of the girls in the survey named
bowling as their favorite sport?
A.) 0.04%
B.) 4%
C.) 12%
D.) 25%

Answers

Answer:

D

Step-by-step explanation:

PLEASE HELP I WILL MARK BRAINLEST IMMEDIATELY!!!

Tyra made 8 fewer
jackets than Zack.
They made 48 jackets
altogether. How many
jackets did Zack make?

Answers

Zack Made 28 and Tyra made 20

Answer:

28

Step-by-step explanation:

40-8= 40 divided by 2 = 20 so zack made 28 jackets

What is the equation of a line that passes through (0, 6) and (6, 0)?
a.y = -x
b.y = x - 6
c.y = x + 6
d.y = -x + 6
PLZ HELP IN A TEST

Answers

F0ck me daddy in my ars
oh YEAH RIGHT THERE OOOOOHHHH

What are the dependent and independent
variables?

Answers

Answer:

The dependent variable depends on the value of some other number also known as the independent variable. Another way to put it is the dependent variable is the output value and the independent variable is the input value. So for y=x+3, when you input x=2, the output is y = 5.

The images are some examples.

PLEASE HELP ASAP IM PANICKING :(((
d. Which of the following statements are true?


The opposite of the opposite of the integer in part (a) is the integer.

The opposite of the opposite of a negative integer is a positive integer.

The opposite of the opposite of zero is undefined.

The opposite of the opposite of any integer is the integer.

Answers

Answer:

A

Step-by-step explanation:

Answer:

it is C

Step-by-step explanation:

1. Mother gave donations worth Php 23 900.50 to the Children Foundation and
Php 32 097.50 to the Home for the Aged from her savings. If she had
Php 60 555.75 in her bag, how much money will be left to her?
What is asked?
What are given?
What operation should be used to solve the problem?
What is the number sentence?
What is the complete answer?​

Answers

Answer:

What is asked? Total amount left to her.

what are the given? Php 32,097.50 , Php 23,900.50 and Php 60,555.75

what operation should be used to solve the problem? Addition and subtraction

what is the number sentence? Php 23, 900.50+Php32, 097.50=n , Php 60, 555.75 - N = M

what is the complete answer? Php 14,557.75 is the total amount left to her.

Compare: 2/3×(9+12)◯15×2/3

Answers

Answer:

[tex]\frac{2}{3}[/tex] (9 + 12) > 15 * [tex]\frac{2}{3}[/tex]

Step-by-step explanation:

[tex]\frac{2}{3}[/tex] (9 + 12) = [tex]\frac{2}{3}[/tex] * 21 = 2 * 7 = 14

15 * [tex]\frac{2}{3}[/tex] = 5 * 2 = 10

14 > 10 ⇒ [tex]\frac{2}{3}[/tex] (9 + 12) > 15 * [tex]\frac{2}{3}[/tex]

b) 144kg in the ratio 1 3.5​

Answers

So you add 13+5=18

Then you do 144/18=8

8x13=104 8x5=40

104+40=144✅

Answer= 104 : 40

Target buys video games for $25/game. They markup the price by 75%. How much do
they charge customers for a videogame? Do not enter a dollar symbol with your
answer.

Answers

9514 1404 393

Answer:

  $43.75

Step-by-step explanation:

The amount of the markup is ...

  $25 × 0.75 = $18.75

The final cost to the customer is ...

  selling price = purchase price + markup

  = $25.00 + 18.75 = $43.75

They charge customers $43.75 for a videogame.

I NEED HELP ASAP PLEASEEEE​

Answers

Answer:

Step-by-step explanation:

1) Find the Mean of all the numbers.

3+4+5+7+10+12+15=56

56/7=8 mean is 8

Now We Calculate Standard Deviation:

S=[tex]\sqrt{(3-8)^2+(4-8)^2+(5-8)^2+(7-8)^2+(10-8)^2+(12-8)^2+(15-8)^2}[/tex]

You take each number from the problem i.e 3,4,5...

and then you subtract the mean from it and then square it.

S=[tex]\sqrt{(-5)^2+(-4)^2+(-3)^2+(-1)^2+(2)^2+(4)^2+(7)^2}[/tex]

S=[tex]\sqrt{25+16+9+1+4+16+49}[/tex]

S=[tex]\sqrt{120}[/tex]

S=[tex]\sqrt{120}/7[/tex]

7 is the amount of data units given in the problem.

120/7=17.1428571429

[tex]\sqrt{17.1428571429}[/tex] =4.1403933560541

Nearest hundredth=4.14

A ____________________ is a measurement of the change in variables over a specific period of time.
Group of answer choices

an ordered pair

graph

table

rate of change

Answers

Answer:

rate of change

Step-by-step explanation:

The rate of change (ROC) is the speed at which a variable changes over a specific period of time.

I need this please help me

Answers

Answer:

y=4/5(x)+10

Step-by-step explanation:

the slope of the line is 4/5 and the y intercept is 10

using the format y=mx+b where m is the slope and b is the y intercept we arrive at the equation

A shade of green paint is made by mixing 2 cups of
yellow with 3.5 cups of blue.
Will a mixture that is 3 cups of yellow and 4.5 cups of
blue be more blue, more yellow, or the same shade of
green?
More blue
More yellow
Same shade
Explain your reasoning.

Answers

Answer:

7

Step-by-step explanation:

2×3.7=7 is easy and less money

Find the area of the figure below

Answers

Step-by-step explanation:

(3×6) + (2×6)

= 18 + 12

= 30 in²

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