In how many ways can we seat 3 pairs of siblings in a row of 7 chairs, so that nobody sits next to their sibling
Answer:
1,968
Step-by-step explanation:
Let x₁ and x₂, y₁ and y₂, and z₁ and z₂ represent the 3 pairs of siblings, and let;
Set X represent the set where the siblings x₁ and x₂ sit together
Set Y represent the set where the siblings y₁ and y₂ sit together
Set Z represent the set where the siblings z₁ and z₂ sit together
We have;
Where the three siblings don't sit together given as [tex]X^c[/tex]∩[tex]Y^c[/tex]∩[tex]Z^c[/tex]
By set theory, we have;
[tex]\left | X^c \cap Y^c \cap Z^c \right |[/tex] = [tex]\left | X^c \cup Y^c \cup Z^c \right |[/tex] = [tex]\left | U \right | - \left | X \cup Y \cup Z \right |[/tex]
[tex]\left | U \right | - \left | X \cup Y \cup Z \right |[/tex] = [tex]\left | U \right | - \left (\left | X \right | + \left | Y\right | + \left | Z\right | - \left | X \cap Y\right | - \left | X \cap Z\right | - \left | Y\cap Z\right | + \left | X \cap Y \cap Z\right | \right)[/tex]
Therefore;
[tex]\left | X^c \cap Y^c \cap Z^c \right | = \left | U \right | - \left (\left | X \right | + \left | Y\right | + \left | Z\right | - \left | X \cap Y\right | - \left | X \cap Z\right | - \left | Y\cap Z\right | + \left | X \cap Y \cap Z\right | \right)[/tex]
Where;
[tex]\left | U\right |[/tex] = The number of ways the 3 pairs of siblings can sit on the 7 chairs = 7!
[tex]\left | X\right |[/tex] = The number of ways x₁ and x₂ can sit together on the 7 chairs = 2 × 6!
[tex]\left | Y\right |[/tex] = The number of ways y₁ and y₂ can sit together on the 7 chairs = 2 × 6!
[tex]\left | Z\right |[/tex] = The number of ways z₁ and z₂ can sit together on the 7 chairs = 2 × 6!
[tex]\left | X \cap Y\right |[/tex] = The number of ways x₁ and x₂ and y₁ and y₂ can sit together on the 7 chairs = 2 × 2 × 5!
[tex]\left | X \cap Z\right |[/tex] = The number of ways x₁ and x₂ and z₁ and z₂ can sit together on the 7 chairs = 2 × 2 × 5!
[tex]\left | Y \cap Z\right |[/tex] = The number of ways y₁ and y₂ and z₁ and z₂ can sit together on the 7 chairs = 2 × 2 × 5!
[tex]\left | X \cap Y \cap Z\right |[/tex] = The number of ways x₁ and x₂, y₁ and y₂ and z₁ and z₂ can sit together on the 7 chairs = 2 × 2 × 2 × 4!
Therefore, we get;
[tex]\left | X^c \cap Y^c \cap Z^c \right |[/tex] = 7! - (2×6! + 2×6! + 2×6! - 2 × 2 × 5! - 2 × 2 × 5! - 2 × 2 × 5! + 2 × 2 × 2 × 4!)
[tex]\left | X^c \cap Y^c \cap Z^c \right |[/tex] = 5,040 - 3072 = 1,968
The number of ways where the three siblings don't sit together given as [tex]\left | X^c \cap Y^c \cap Z^c \right |[/tex] = 1,968
hhhhhhhhhheeeeeeeeeeeeeeeeellllllllllllllllllllllppppppppppppp
Answer:
40°
Step-by-step explanation:
As sum of angles of the triangle is 180°
therefore the third angle will be 180 -( 75 + 65)=40°
x=40°= vertically opposite angle
Answer:
x = 40°
Step-by-step explanation:
a + 65 + 75 = 180 {Angle sum property}
a + 140 = 180
a = 180 - 140
a = 40
x = a {Vertically opposite angles}
x = 40°
[tex]solve : - \\ \\ factorise \: (x {}^{2} + 30x + 216) \\ \\ please \: help \: [/tex]
Answer:
[tex](x+12)(x+18)[/tex]
Step-by-step explanation:
[tex] {x}^{2} +30x+216[/tex]
[tex](x+12)(x+18)[/tex]
Hope it is helpful....x²+30x+216
on factorizing we get
(x+12)(x+18)
Therefore, x= -12 or -18
BRAINlIEST FOR CORRECT ANSWER
Answer:
ok
Step-by-step explanation:
mark me the brainlieast since your question is incomplete
please help guys !!!
Answer:
[tex] \frac{1}{4} \: \: \: \frac{1}{3} \: \: \: \frac{1}{2} \: \: \: \frac{7}{12} \: \: \: \frac{3}{4} [/tex]
Step-by-step explanation:
To arrange in ascending order, first make the denominators of all the fractions the same.
LCM of 2, 3, 4 and 12 is 12.
Now,
[tex] \frac{1}{3} = \frac{4}{12} [/tex]
[tex] \frac{3}{4} = \frac{9}{12} [/tex]
[tex] \frac{1}{4} = \frac{3}{12} [/tex]
[tex] \frac{7}{12} \: \: will \: be \: \: \frac{7}{12} [/tex]
[tex] \frac{1}{2} = \frac{6}{12} [/tex]
Arranging these in ascending order:
[tex] \frac{3}{12} \: \: \: \frac{4}{12} \: \: \: \frac{6}{12} \: \: \: \frac{7}{12} \: \: \: \frac{9}{12} [/tex]
A 0.25 mL sample of water drawn from a 5 liter flask contains 1.25 x 10^8 bacteria. Give the approximate number of bacteria in the flask, expressing your answer in scientific notation.
(Scientific Notation: find a real number a between 1 and 10, and an integer n, such that x = a x 10^n.)
Answer:
The number of bacteria in 0.25 mL is 6.25 x 10^3.
Step-by-step explanation:
5 liter flask contains 1.25 x 10^8 bacteria.
So, 1liter flask contains = [tex]\frac{1.25 \times 10^8}{5} =2.5\times 10^7[/tex]
Now
0.25 mL contains = [tex]2.5\times 10^7 \times0.25\times 10^{-3} = 6.25\times 10^3[/tex]
pls help me in these questions
Answer:
1=85
2=10
3=108
Step-by-step explanation:
Number 1: Calculate each angle...and you know a straight line is 180°. N the interior sum of a quadrilateral is always 360°.
Number2: Use corresponding, alternate and interior angles method. It will help
Number 3: It's just about solving the interior sum of the pentagon
Answer:
2. 10 degrees
3. 108 degrees
Step-by-step explanation:
sorry I reposted it because the previous answer was deleted and plz mark me as a brainliest.
Hiệu điện thế giữa hai điểm M và N là UMN = 100 V. Một điện tích q = -2μC di chuyển từ M đến N thì công của lực điện là:
Answer:
The work done is - 200 μJ.
Step-by-step explanation:
The potential difference between two points M and N is UMN = 100 V. A charge q = -2μC moves from M to N, the work of the electric force is:
Potential difference, V = 100 V
Charge, q = - 2 μC
The potential difference is defined as the amount of work done in bringing a unit positive test charge from one point to another in the electric field.
So, W = q V
W = - 2 μC x 100 V = - 200 μJ
Find the measure of the missing angle using the triangle angle sum theorm
Answer:
31°
Step-by-step explanation:
The theorem states that all angle sums of any triangle add up to 180°.
128 + 21 = 149, and to find ?°, subtract 149 from 180 to get 31°.
Given the triangle below, what is mA, rounded to the nearest tenth?
Answer:
A. 24.2°
Step-by-step explanation:
I'm correct if I'm rwong
Four graphs are shown below:
Scatter plot A shown with data points that move in an upward direction and are located at 1 and 0.3, 2 and 1, 3 and 2, 4.1 and 4, 5.2 and 6.1, 5.9 and 9.5. Additional points are located at 4.6 and 5, 5.8 and 7.4, 5.2 and 7.1. Scatter plot B is shown with data points that move in an upward direction and are located at 1 and 3, 2 and 4, 3 and 5, 4 and 6, 5 and 6, 6, and 7, 7 and 8, 8 and 9. Scatter plot C is shown with data points that move in a downward direction and are located at 1 and 8.7, 4 and 5.6, 5 and 4.3, and 6 and 0.5. Additional points are located at 5.9 and 1.5, 5.5 and 3.5. Scatter plot D is shown with data points that move in a downward direction and are located at 0 and 7, 1 and 6, 2, and 5, 3 and 4, 4 and 3, 5 and 4, 6, and 5.
Which graph represents a negative linear association between x and y?
Graph A
Graph B
Graph C
Graph D
Answer:
graph D
Step-by-step explanation:
because d it at 0 then moves
Answer:
a
Step-by-step explanation:
Does the point (7, 2) satisfy the equation y = x - 5? yes no
Yes
Replace x in the equation with the x in the solution and see if t equals the y in the solution:
Y = 7-5 = 2
The answer is yes.
Which must be true of a quadratic function whose vertex is the same as its y-intercept?
Answer:
A
Step-by-step explanation:
because y-intercept is when x=0, so right on the y axis.
Please someone help I can not get past this question
Answer:
65.76 m
Step-by-step explanation:
This figure is split into three shapes: a right triangle, a rectangle, and a semi- circle. To find the area of the figure you can start by figuring out the area of each of the three shapes mentioned above, then adding their areas together. I'll write the numbers without the unit to make it simpler since it won't cancel out or anything.
Starting with the triangle:
1/2(b*h)=a
We see the base is 3, and the height is 5 (because the two opposite sides of a rectangle will be congruent) so if you plug the numbers into the formula you get:
1/2*15=a or 15/2=a
a=7.5
Then we calculate the area of the rectangle:
l*w=a
5*6=a
30=a
Then the area of the semi circle:
First we find the area as if it were a full circle by the equation using 3.14 as pi and 3 as r (since the denominator is 6 and half of 6 is 3):
3.14*r^2=a
3.14*3^2=a
3.14*9=a
28.26=a
Finally, we add all three areas from above:
7.5+30 + 28.26 = 65.76
Evaluate i^15 i^12
Show work
Answer: 15 = -i & 12=1
use the pattern : i, -1, -i, 1
Step-by-step explanation:
i = [tex]\sqrt{-1}[/tex]
[tex]i^{2}[/tex] = [tex]\sqrt{-1}[/tex]
[tex]i^{3}[/tex] = [tex]\sqrt{-1}[/tex]
[tex]i^{4}[/tex] = [tex]\sqrt{-1}[/tex]
the pattern just repeats from here
5 = i
6 = -1
7 = -i
8 = 1
9 = i
10 = -1
11 = -i
12 = 1
13 = i
14 = -1
15 = -i
16 = 1
resolver:
[5+(-3+6)+(-2)]-[(-4+10)+(-3)-(-5)]
Two exponential functions are shown in the table.
х
f(x)=2*
g(x)=
1
2
2
4
1
4
Which conclusion about f(x) and g(x) can be drawn from
the table?
O The functions f(x) and g(x) are reflections over the x-
axis.
O The functions f(x) and g(x) are reflections over the y-
axis.
O The function f(x) is a decreasing function, and g(x) is
an increasing function.
O The function f(x) has a greater initial value than g(x).
1
2
OT
1
2
1
2
1
1
2
1
4
-2.
4
The true statement about the exponential functions is (b) the functions f(x) and g(x) are reflections over the y-axis.
The functions are given as:
[tex]f(x) = 2^x[/tex]
[tex]g(x) = (\frac 12)^x[/tex]
Reflect function over the y-axis.
The rule of this transformation is:
[tex](x,y)\to (-x,y)[/tex]
So, we have:
[tex]f(x) = 2^x[/tex]
[tex]f'(x) = 2^{-x}[/tex]
Apply power rule of indices
[tex]f'(x) = (\frac{1}{2})^x[/tex]
By comparison:
[tex]g(x) = f'(x) = (\frac{1}{2})^x[/tex]
Hence, the functions f(x) and g(x) are reflections over the y-axis.
Read more about function transformation at:
https://brainly.com/question/1548871
CAN SOMEBODY PLEASE HELP MEEEE
Answer:
105.
Step-by-step explanation:
.
which of the following is a geometric sequence
A. 6, 18, 54, 162
B. 1, 4, 5, 9, 14
C. 3, 6, 9, 12, 15
D. 3, 5, 8, 13, 21
c) What should be subtracted from 5m - 3n to get 2m + 5n?
What she hechosomoce 2-59
Answer:
3m-8n
Step-by-step explanation:
Set up an equation:
(5m-3n)-(2m+5n) = ?
Solve:
5m-3n
- 2m+5n
3m-8n
Hope this helps!
Between 20 to 35 degrees north latitude, and also between 20 to 35 degrees south latitude are found:
Answer:
Following are the solution to the given question:
Step-by-step explanation:
Its area includes all Sahara's locations in North Africa, South Arabia, Iran's and Iraq's larger parts, North-Western India, California throughout the United States, South Africa but most of Australia.
Half-arid temperatures include places like the Utah, Montana, and Gulf Coastal regions of sagebrush. Also, it comprises regions in Iceland, Russia, Scandinavia, Greenland, and Northeast India. Semi-arid thankless than tube called per year of rain and up to 20 inches per year at much more than arid deserts.
Regions from of the latitude of 25° to 35° usually develop desert, because air sinks and is heated under pressures in this area. The world's dry and semi-arid desert regions are between 20°C and 35°C north latitude and between 20°C and 35°C South latitude.
D=22/7×d-90 Solve the equation
Find D
Fast!
Answer:
D=22-90+22d/7
Step-by-step explanation:
D=22/7×d-90
D=-90+22d/7
Directions: Given the point and slope, write the equation of the line.
(4, 2); slope = 36
Answer:
y - 2 = 36(x - 4)
Step-by-step explanation:
The equation of a line in point- slope form is
y - b = m(x - a)
where m is the slope and (a, b) a point on the line
Here m = 36 and (a, b ) = (4, 2 ) , then
y - 2 = 36(x - 4) ← equation of line
If the measure of < A is 99 ° and the measure of < B is 81 ° , then < A and < B are _____.
Select one:
a. complementary angles
b. adjacent angles
c. vertical angles
d. supplementary angles
Answer:
D.supplementary angles
Step-by-step explanation:
81+99=180
daca cel mai mare divizor comun al lor a si b este 21 iar produsul lor este 15435 cat sunt a si b
Answer:
[tex]{\dag{\underline{{\sf{\red{t {}^{2} = \: \dfrac{4.05}{5} \: = 0.81 \: , \: \: t = 0.9s}}}}}}[/tex]
The area of a rectangle is 35ft^2 , and the length of the rectangle is 3 ft more than twice the width. Find the dimensions of the rectangle.
Answer:
1228 is your answer
Step-by-step explanation:
HELPPPPPPPPPPPPPPPP SOMEONE !!!What is the rate of change of the amount earned with respect to hours worked for this function?
hours per dollar
hours per dollar
3 dollars per hour
13 dollars per hour
Answer:
$13 per hour
Step-by-step explanation:
This is because 26÷2=13, 65÷5=13
Pls help before the clock hits 50 :(
Use the following graph of the function f(x) = 3x4 − x3 + 3x2 + x − 3 to answer this question: What is the average rate of change from x = -1 to x = 0
Answer:
-6
Step-by-step explanation:
3x + y = 10 x - y = 2 2
Question 2: use the image and your knowledge of the isosceles triangle to find the value of x
Answer:
x is 66 degrees
Step-by-step explanation:
since its a isosceles, two of the angles should be the same.
