Can anyone help with this pleases

See the link in comments (or if it gets deleted, look up "partial derangement"). The number of ways in which exactly [tex]k[/tex] items from a pool of [tex]n[/tex] items can be rearranged such that only these [tex]k[/tex] items are in their original positions is

[tex]R(n,k) = \dbinom nk \, !(n-k)[/tex]

where [tex]!(n-k)[/tex] is the so-called sub-factorial that satisfies the relation

[tex]!n = \left\lfloor \dfrac{n!+1}e \right\rfloor[/tex]

and [tex]\lfloor x \rfloor[/tex] denotes the floor or greatest integer function of [tex]x[/tex], i.e. the greatest integer smaller than or equal to [tex]x[/tex].

There are 25! ways of handing back exams with no extra constraint.

There are [tex]R(25,23)[/tex] ways of handing back 23 exams to their original owners and 2 exams otherwise, and

[tex]R(25,23) = \dbinom{25}{23} \, !(25-23) = 300\left\lfloor\dfrac{2!+1}e\right\rfloor = 300[/tex]

Then the probability of returning 23 exams correctly and 2 exams swapped is

[tex]\dfrac{300}{25!} \approx \boxed{5.17\times10^{-22}}[/tex]

Answer:

x⁷⁶ + 2401

Step-by-step explanation:

When an exponent is raised to another exponent, the two exponent values are multiplied. When a number is raised to an exponent, the number is multiplied by itself that many of times.

(x¹⁹ + 7)⁴  ---->

x⁽¹⁹ ˣ ⁴⁾ + 7⁴  --->  

x⁷⁶ + (7 x 7 x 7 x 7)  --->

x⁷⁶ + 2401

Answer:

2048 or D

Step-by-step explanation:

We can use the formula c=(pi)(d)

replace 6,430.72 with c!

c=(pi)(d)

6,430.72=3.14*d

- Divide both sides by 3.14 -

d = 2048

Answer:

  2436

Step-by-step explanation:

The sum of n terms of an arithmetic series is given by the formula ...

  Sn = (n/2)(2a +d(n -1))

where a is the first term, and d is the common difference.

__

This series has ...

  a = 46

  d = 53 -46 = 7

  n = 21

So, the desired sum is ...

  S21 = (21/2)(2(46) +7(20)) = 2436

The sum of the first 21 terms is 2436.

Answer:

The numbers less than 50 (A) = 4

Total numbers (S) = 14

Probability students below 50 = 4÷14

Step-by-step explanation:

That is the correct answer of it.

Answer:

53 meters

Step-by-step explanation:

5300 / 100 = 53

because yes

Answer:

(-1,-2)

Step-by-step explanation:

The given coordinates are ,

G ( 4 , 10)

H ( -2 , -6)

Midpoint can be calculated by finding the mean of x coordinates and y coordinates . As ,

→ Midpoint = ( 4-2/2 , 10-6/2)

→ Midpoint = ( -2/2 , -4/2 )

→ Midpoint = ( - 1 , -2)

To find out the midpoint,here's the formula: ((x1+x2)÷2 , (y1+y2)÷2)

Thus,the midpoint of QS is

((4+(-2))÷2 , (10+3)÷2)

=(1 , 13/2)

hope it helps!

Answer:

D

Step-by-step explanation:

Answer: 234 in sq.

Step-by-step explanation: Volume = length times width times height.

13 x 9 x 2 = 234 in sq.

Hope this helps.

Answer:

1533.88261311522

Step-by-step explanation:

Let r be the radius of the (base/circle)

and  L be the slant height of the cone

Formula ………………………………………………………………………………………………………

The surface area of a cone = the (curved/lateral) surface area +  the base

                                             [tex]=\pi r^{2}\ \ \ +\ \ \ \pi Lr[/tex]

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

[tex]r=\frac{21}{2} =10.5[/tex]

L = BC = 36

[tex]\text{surface area} =\pi \left( 10.5\right)^{2} +\pi \times 36\times \left( 10.5\right)[/tex]

                   [tex]=346.360590058275 + 1187.52202305694[/tex]

                   [tex]=1533.88261311522[/tex]

Answer:

  x = 4

Step-by-step explanation:

The base angles of an isosceles triangle are congruent, as shown in the figure.

Equating their measures, we have ...

  ∠A = ∠C

  8x -7 = 25 . . . . substitute the given expressions

  8x = 32 . . . . . add 7

  x = 4 . . . . . . divide by 8

Answer:

she only has saved 28 3 times according to the data

Step-by-step explanation:

Answer:

hope this will help you

Step-by-step explanation:

[tex] \frac{7m}{4} - 2m - 3 \\ = \frac{7 \times ( - 2)}{4} - 2 \times ( - 2) - 3 \\ = \frac{ - 7}{2} + 4 - 3 \\ = \frac{ - 7}{2} + 1 \\ = \frac{ - 7 + 2}{2} \\ = \frac{ - 5}{2} \\ = - 2.5[/tex]

[tex](3 + {n}^{4} ) \div 3 \\ = (3 + {3}^{4} ) \div 3 \\ = (3 + 81) \div 3 \\ = 84 \div 3 \\ = 28[/tex]

1. 83.92

2.15.88

3. 19.66

Answer:A

Step-by-step explanation:

Answer:

answer is A

Step-by-step explanation:

yes A

the answer is 153.86 ft squared

= the formula for the area of a circle is A=πr2

= area = pi x radius squared

= the radius is 7 feet, square that to get 49

= multiply 49 by pi to get the area: 153.86 square feet

153.86 ft squared

Answer:

153.86 ft squared

Step-by-step explanation:

As per given question we have provided that :

We need to find :

Here's the required formula :

[tex]{\dashrightarrow\sf{A = \pi {r}^{2}}}[/tex]

Substituting all the given values in the formula to find the area of circular pool :

[tex]{\dashrightarrow{\sf{Area = \pi {r}^{2}}}}[/tex]

[tex]{\dashrightarrow{\sf{Area = 3.14{(7)}^{2}}}}[/tex]

[tex]{\dashrightarrow{\sf{Area = 3.14{(7 \times 7)}}}}[/tex]

[tex]{\dashrightarrow{\sf{Area = 3.14{(49)}}}}[/tex]

[tex]{\dashrightarrow{\sf{Area = 3.14 \times 49}}}[/tex]

[tex]{\dashrightarrow{\sf{Area = 153.86}}}[/tex]

[tex]\star{\underline{\boxed{\sf{\red{Area = 153.86 \: {ft}^{2}}}}}}[/tex]

Hence, the area of circular pool is 153.86 ft².

[tex]\rule{300}{1.5}[/tex]

The weights that represent 90% of the weight of a four years old boy will be 44.58

The z-score is a statistical evaluation of a value's correlation to the mean of a collection of values, expressed in terms of standard deviation.

The weights of four years old boys are normally distributed with a mean of 38 pounds and a standard deviation of 4 pounds.

The value of the z-score at 90% will be 1.645

Then the weights that represent the 90% of the weight of a four year old will be

1.645 = (x - 38)/4

6.58 = x - 38

      x = 44.58

More about the normal distribution link is given below.

https://brainly.com/question/15016913

#SPJ1

Answer:

Shade in 5 parts of the 10 strip.

Step-by-step explanation:

I didn't get an image but what I think the problem looks like is this, 10 empty strips, but just fill in 5, then it looks like the second image.

Answer:

x = -3 2/3

have a great day

Answer:

x = -3 2/3

Step-by-step explanation:

Answer:

6 inches

Step-by-step explanation:

105÷35=3

3x2=6

Answer:

1 AM

Step-by-step explanation:

9AM(start time) to 9PM = 12 hours + the other 4 Hours, 10PM, 11PM, 12PM, 1AM(end time).

Answer:

1. x=44°

2.5x=50°

3x=30°

Step-by-step explanation:

1) 46°+x=90°

x=90-46= 44°

X= 44°

2) 5x+100°+3x=180°

8x+100=180

8x=180-100

8x=80

x=80/8

x=10

substitute the value of x in '3x' and '5x'

3*10=30

5*10= 50

Answer:

the sum of the measures of it's angles is 180

Answer:

x = -4

Step-by-step explanation:

First Expand :

6(x - 3)

= 6x - 18

Now you need to Simplify:

6x - 18 = -42

And now get the 6x by itself by doing this :

6x - 18 = -42

+18 +18

= > 6x = -24

And 6 x 4 = 24

But 6 x -4 = -24

So :

6x/6 and -24/6

= >> x = -4

Answer:

D. Distance

Step-by-step explanation:

Distance is measured to determine the winner of the shot-put competition

- AKIA

Answer:

It is increasing

The y-intercept is (0, 3).

The domain of F(x) is all real numbers.