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ruslelena [56]
3 years ago
9

9 friends are lining up. Joe, Susan, John, and Meredith must be beside each other. How many ways can they line up?

Mathematics
1 answer:
ZanzabumX [31]3 years ago
6 0
<h3>Answer:  17,280</h3>

This is one single number slightly over 17 thousand.

You may need to erase the comma when typing the answer in.

=========================================================

Explanation:

Let's say that another person steps in for Joe, Susan, John, and Meredith. I'll refer to this person as the teacher (perhaps these 9 friends are students on a field trip).

The 9 friends drops to 9-4 = 5 people when those four named people leave the group temporarily. Then it bumps up to 5+1 = 6 people when the teacher steps in. Wherever the teacher is located, the four friends that left will replace the teacher. This guarantees that those four friends stick together.

There are 6! = 6*5*4*3*2*1 = 720 ways to arrange those 6 people. The exclamation mark is a factorial symbol.

Within any of those 720 permutations, we have 4! = 4*3*2*1 = 24 ways to arrange those group of named people when they come back to replace the teacher.

So overall the answer is 4!*6! = 24*720 = 17,280

You may need to erase the comma when typing the answer in.

-------------

Side note: There are 9! = 362,880 ways to arrange all nine friends regardless if those four mentioned people stick together or not. We see that they stick together roughly (17,280)/(362,880) = 0.0476 = 4.76% of the time.

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Hello!! Plz ans with explanation.. Plz!! I need it ASAP!!! PLZ TYSM<br>Faaast!!
jonny [76]

Answer:

1/4

1/2

3/4

Step-by-step explanation:

<u>Given</u><u>:</u>

Types of colors in the spinner

Yellow 1

Red 2

Blue 1

Total:4

Successful outcome of Yellow:1

Successful outcome of Red:2

Successful outcome of Blue:1

<u>Required</u><u>:</u>

Probability of the

  • blue sector
  • red sector
  • not on yellow sector

<u>Formula</u><u>:</u>

Probability= successful outcome ÷ possible outcome

<u>Solution</u><u> </u>

  • Blue sector

Probability=1 ÷ 4

  • Red sector

Probability= 2÷4

  • not on yellow sector

Probability= 3÷4

Hope this helps ;) ❤❤❤

7 0
3 years ago
What are the solution(s) of x^2-4=20?
Pie

x^2-4=20\qquad|+4\\\\x^2=24\to x=\pm\sqrt{24}\\\\x=-\sqrt{4\cdot6}\ \vee\ x=\sqrt{4\cdot6}\\\\x=-2\sqrt6\ \vee\ x=2\sqrt6

4 0
2 years ago
The original price of the air conditioner was $400. Give your answer as a percentage.
Zigmanuir [339]

Answer: 100%

Step-by-step explanation:

If the original price is $400, that will be 100%.

8 0
3 years ago
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2 poin
Olegator [25]

Answer:

50 or more

Step-by-step explanation:

6 0
2 years ago
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Solve the equation for x.
ivann1987 [24]

Answer:

x = 44

Step-by-step explanation:

sqrt(x+5) -3 =4

Add 3 to each side

sqrt(x+5) -3+3 =4+3

sqrt(x+5)  =7

Square each side

(sqrt(x+5))^2  =7^2

x+5 = 49

Subtract 5 from each side

x+5-5 = 49-5

x=44

3 0
3 years ago
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