Mathematics High School

Permutations acellus How many ways can 4 books be arranged on a shelf if there are 8 books to chose from? Note: nPr = n! —— (n-r)!

Answers

Answer 1

Answer:

1680 ways

Step-by-step explanation:

From the question,

nPr = n!/(n-r)!.................. Equation 1

Where, n = Total number of books to chose from, r = number of books to be arranged in the shelf.

Given: n = 8 books, r = 4 books.

Substitute into equation 1

8P4 = 8!/(8-4)!

8P4 = 8!/4!

8P4 = (8×7×6×5×4!)/4!

8P4 = 1680 ways.

Hence the number of ways 4 books can be arranged in a shelf if there are 8 books to chose from is 1680 ways

Related Questions

please solve Y Im in desperate need of help..

Answers

Answer:

Y = 10

Explanation:

We know that the left and top angles are 45°, the base is 10, and the bottom right angle is 90°, or a right angle. The simplest way I can explain this is the bottom side of the triangle is the same as the right side of the triangle. Meaning "y" would be 10 like the bottom.

If I'm right, I'd appreciate a brainliest as it'd really help me out :D

I HELP NEED ASAP PLZ HELP ME

Answers

Step-by-step explanation:

hope it helps.........

Answer:

The answer is 6.

Step-by-step explanation:

All you need to do is turn 33 and 44 into a fraction ([tex]\frac{33}{44}[/tex]). Then you need to simplify it and it's simplest form is [tex]\frac{3}{4}[/tex]. then you up the fraction to [tex]\frac{6}{8}[/tex] and that's your answer.

7-4 pls help pleasssssssssssssssse

Answers

Answer:

for what subject?

geometry

trig

algebra

Answer:

I think it's 3 but maybe ask your teacher to check :o

Step-by-step explanation:

Find the value of X?

Answers

Answer:

Using this to get my answer done ;)

Step-by-step explanation:

hehe

The value of X would be 18

(2p^3 · 2p)^2
HELLO I NEED HELP

Answers

Answer:

Step-by-step explanation:

Here are some steps to help you

Step 1

(2p^3 · 2p)^2 We are gonna be simplifying

(4p^4)^2

Step 2

(4p^4)(4p^4)

16p^8

So therefore your answer would be 16p^8

Hope this helps

El largo de una casa es el triple de su ancho. Si a la longitud se suma 40 metros y al ancho 1 metro, el área se triplica

Answers

Answer:

el ancho es de 8 metros y el largo es 3 * 8 = 24 metros

width is 8 meters and length is 3*8= 24 meters

Step-by-step explanation:

Spanish

Si el ancho de la casa de la casa es x, entonces el largo de la casa es 3x.

Entonces el área = largo * ancho

área = 3x * x = 3x²

3 multiplicado por área = 9x²

9x² = (3x + 40) (x + 1)

9x² = 3x² + 3x + 40x +40

9x² = 3x² + 43x +40

0 = -6x² + 43x +40

0 = 6x²- 43x - 40

6x²- 43x - 40 = 0

Usando ecuación cuadrática

a = 6, b = -43, c- = -40

x = - b ± √b²- 4ac / 2a

x = 43 ± √1849- 4 (6) (- 40) / 12

x = 43 ± √1849 + 960/12

x = 43 ± 53/12

x = 43+ 53/12 y x = 43-53 / 12

x = 96/12 y x = -10/12

x = 8 y x = - 5/6

Ignorando el valor negativo x = 8 el ancho es de 8 metros y el largo es 3 * 8 = 24 metros

English

The length of a house is three times its width. If 40 meters are added to the length and 1 meter to the width, the area is tripled

If the width of the house of the house is x then the length of the house is 3x.

Then the area = length * breadth

area= 3x*x= 3x²

3 times area= 9x²

9x²= (3x+40 )(x+1)

9x²= 3x²+ 3x +40x +40

9x²= 3x²+ 43x +40

0 = -6x²+ 43x +40

0 = 6x²- 43x - 40

6x²- 43x - 40= 0

Using quadratic equation

a= 6 , b= -43 , c-= -40

x= - b±√b²- 4ac/ 2a

x= 43±√1849- 4(6)(-40)/ 12

x= 43±√1849+960/ 12

x= 43± 53/ 12

x= 43+ 53/ 12 and x= 43- 53/ 12

x= 96/ 12 and x= -10/ 12

x= 8 and x= - 5/6

Ignoring the negative value x= 8 width is 8 meters and length is 3*8= 24 meters

Winston earns $140.00 by selling 56 hot dogs at a concession stand at school. Using the same rate for the cost of one hot dog, How many more hot dogs would Winston needto sell to earn a total of $175.00 ?

Answers

Answer:

Winston would need to sell 14 more hot dogs to earn a total $175

Step-by-step explanation:

pLEASE HELP I'LL GIVE BRAINLIEST

Answers

Hope it helps you......

What is the slope of a line that passes through the points (12,7) and (-14,19)?
F) -13/6
G) -1
H) -6/13
J) 3

Answers

Answer:

H) -6/13

Step-by-step explanation:

To find the slope of the line between a pair of two points, use the slope formula, [tex]m = \frac{y_2-y_1}{x_2-x_1}[/tex]. Substitute the x and y values of (12,7) and (-14,19) into the formula and simplify like so:

[tex]m = \frac{(19)-(7)}{(-14)-(12)} \\m =\frac{19-7}{-14-12} \\m = \frac{12}{-26} \\m = -\frac{6}{13}[/tex]

So, Option H is correct.

Based on a random sample of 500 people, 45 reported they have more than one
dog. Based on these results, how many out of 1,200 people would you expect to
have more than one dog?
A
1,008
B
60
С
165
D
108

Answers

Answer:

I’m guessing 108 or 165

Step-by-step explanation:

because if 45/500 if you double that it would be 90/1000. after 200 is about half of 500 so 45 divided by 2 is 22.5. yeah i’m like no help sorry

Sara is packing for vacation she is taking three shirts: yellow (y) white (w) and green (g) she is also taking a pair of jeans (j) a pair of black pants (b) and pair of shorts (s) for shoes, she is packing tennis shoes (t) and a pair of dress shoes (d) each outfit will be made of 1 shirt 1 pair of pants and 1 pair of shoes

Answers

Answer:

She has 18 combinations to choose from

Step-by-step explanation:

The tree diagram is as follows

yellow (y) ⇒⇒⇒⇒⇒ a pair of jeans (j)

║ ║⇒⇒⇒⇒⇒⇒⇒⇒⇒tennis shoes (t)