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Gwar [14]
2 years ago
9

Suppose you want to count the number of​ four-letter passwords that can be formed using the letters in the word NUMBER. The four

letters in the password must all be different. Which of the following expressions is true concerning the number of such​ passwords? (A) There are 10 x 9 x 8 x 7 possibiities (B) It is combination question(C) There are 10000 possibilities(D) The password must not follow order matter
Mathematics
1 answer:
WITCHER [35]2 years ago
6 0

Answer:

D.The password must not follow order matter

Step-by-step explanation:

We are given that suppose you want to count the number of four letters password that can be formed using the letters in the word NUMBER.

We are given that all letters in the password must be all different .There is no nothing saying about order so we can make combination without order .

We have to find the number of 4- letter password that can be formed using letters in the word NUMBER.

By using Permutation formula we find the number of 4- letters password that can be formed by using the letters N,M,B,U,E,R.

Permutation formula : The number of arrangements when taken r objects at a time out of n objects

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

Total letters in word NUMBER=N,U,M,B,E,R=6

n=6,r=4

Therefore, the number of arrangements  can be made from 6 letters when 4 letters taken at a time =\frac{6!}{(6-4)!}

The number of selection can be made from 6 letters when 4 letters taken at a time =\frac{6!}{(6-4)!}

The number of selection can be made from 6 letters when 4 letters taken at a time =\frac{6\times5\times 4\times3 \times 2!}{ 2!}

n!=n(n-1)(n-2)(n-3)...........3\cdot.2\cdot.1

The number of selection can be made from 6 letters when 4 letters taken at a time =360

Option D is correct.

Answer : D.The password must not follow order matter

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lbvjy [14]

First of all, a bit of theory: since the area of a square is given by

A = s^2

where s is the length of the square. So, if we invert this function we have

s = \sqrt{A}.

Moreover, the diagonal of a square cuts the square in two isosceles right triangles, whose legs are the sides, so the diagonal is the hypothenuse and it can be found by

d = \sqrt{s^2+s^2} = \sqrt{2s^2} = s\sqrt{2}

So, the diagonal is the side length, multiplied by the square root of 2.

With that being said, your function could be something like this:

double diagonalFromArea(double area) {

double side = Math.sqrt(area);

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1 year ago
A company has five warehouses, only two of which have a particular product in stock. A salesperson calls the five warehouses in
Kaylis [27]

Answer: Check the attached

Step-by-step explanation:

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2 years ago
A test tube contains 25 bacteria, 5 of which are can stay alive for atleast 30 days, 10 of which will die in their second day. 1
boyakko [2]

Answer:

c. \frac{1}{5}

Step-by-step explanation:

Given,

Number of bacterias who alive for at least 30 days = 5,

Bacterias who alive for 2 days = 10,

Died bacterias = 10,

Total bacterias = 5 + 10 + 10 = 25,

Ways of choosing a bacteria = ^{25}C_1 = \frac{25!}{1! 24!} = 25,

While, ways of choosing of a bacteria who will live after 1 week = ^5C_1 = \frac{5!}{1!4!} = 5,

Hence, the probability it will still be alive after one week = \frac{5}{25} = \frac{1}{5}

OPTION C is correct.  

3 0
1 year ago
The volume of a cone is 3πx3 cubic units and its height is x units.
GaryK [48]

Answer:

It is given that the volume of a cone = 3 \pi x^{3} cubic units

Volume of cone with radius 'r' and height 'h' = \frac{1}{3} \pi r^{2}h

Equating the given volumes, we get

3 \pi x^{3}=\frac{1}{3} \pi r^{2}h

r^{2} h =3 \times 3 x^{3}

r^{2} h =9 x^{3}

It is given that the height is 'x' units.

Therefore, r^{2} x =9 x^{3}

r^{2} =9 x^{2}

Therefore, r = 3x

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8 0
2 years ago
Read 2 more answers
Alexa borrowed some money from her friend in order to help buy a new video game system. Alexa agreed to pay back her friend $10
Ulleksa [173]

Answer:

L(t) = 170 - 10t

Step-by-step explanation:

The amount that Alexa owes after t weeks is given by a linear equation in the following format:

L(t) = L(0) - bt

In which L(0) is the initial amount borrowed and b is how much is paid per week.

Alexa agreed to pay back her friend $10 per week and originally borrowed $170.

This means that, respectivelly, b = 10, L(0) = 170. So

L(t) = L(0) - bt

L(t) = 170 - 10t

7 0
1 year ago
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