This question is incomplete, the complete question is;
In a survey, 55% of the voters support a particular referendum. If 40 voters are chosen at random,
find the mean and variance for the number of voters who support the referendum.
Answer:
a) The Mean is 22
b) Variance is 9.9
Step-by-step explanation:
Given that;
55% of the voters support a particular referendum p = 0.55
q = 1 - p = 1 - 0.55 = 0.45
sample size n = 40
a)
Mean = sample size n × p
Mean = 40 × 0.55
Mean = 22
Therefore the Mean is 22
b)
Variance = n × p × q
so we substitute
Variance = 40 × 0.55 × 0.45
Variance = 9.9
Therefore the Variance is 9.9
In a particular game, the probability of winning $95 is 1/36 and the probability of losing $7 is 35/36. What is the expected value after playing this game? Round to the nearest cent.
Answer:
1.53
Step-by-step explanation:
1
36
(
85
)
+
(
35
36
)
(
−
4
)
=
E
V
85
36
−
140
36
=
E
V
−
55
36
=
E
V
E
V
≈
−
$
1.53
Insurance companies are interested in knowing the population percent of drivers who always buckle up before riding in a car. When designing a study to determine this population proportion, what is the minimum number of drivers you would need to survey to be 95% confident that the population proportion is estimated to within 0.05?
If it was later determined that it was important to be more than 95% confident and a new survey was commissioned, how would that affect the minimum number you would need to survey? Why?
a. If the confidence level is increased, then the sample size would need to increase because a higher level of confidence increases the margin of error.
b. If the confidence level is increased, then the sample size would need to decrease because increasing the sample size would create an even larger interval.
c. If the confidence level is increased, then the sample size would need to decrease because we would like the proportion of people who buckle up to be around 50%.
d. If the confidence level is increased, then the sample size would not be affected.
Answer:
The value is [tex]n = 384 [/tex]
The correct option is a
Step-by-step explanation:
From the question we are told that
The margin of error is E = 0.05
From the question we are told the confidence level is 95% , hence the level of significance is
[tex]\alpha = (100 - 95 ) \%[/tex]
=> [tex]\alpha = 0.05[/tex]
Generally from the normal distribution table the critical value of is
[tex]Z_{\frac{\alpha }{2} } = 1.96[/tex]
Generally since the sample proportion is not given we will assume it to be
[tex]\^ p = 0.5[/tex]
Generally the sample size is mathematically represented as
[tex]n = [\frac{Z_{\frac{\alpha }{2} }}{E} ]^2 * \^ p (1 - \^ p ) [/tex]
=> [tex]n = [\frac{ 1.96 }{0.05} ]^2 *0.5 (1 - 0.5) [/tex]
=> [tex]n = 384 [/tex]
Generally the margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} } * \frac{\sigma }{\sqrt{n} }[/tex]
Generally if the level of confidence increases, the critical value of [tex]\frac{\alpha }{2}[/tex] increase and from the equation for margin of error we see the the critical value varies directly with the margin of error , hence the margin of error will increase also
So If the confidence level is increased, then the sample size would need to increase because a higher level of confidence increases the margin of error.
Emile paid $3.96 for 4 songs.
What is the unit rate and what does it mean?
Enter your answers in the boxes.
Answer:
$0.99
Unit rate is cost for 1 individual (song)
Step-by-step explanation:
$3.96/4
0.99
99 cents
what is equivalent to x+x ?
a)xx
b)2x
c)x^2
d)2^x
Answer:
b
Step-by-step explanation:
I think it is B because x+x is two x's so it would be 2x. I hope this helped have a good day
I WILL REWARD BRAINLIEST OKAY IM BEGGING YOU HELP ME
IN THAT PHOTO WHAT ARE THE X AND Y INTERCEPTS!?! WAIT DON'T LOOK AT THE PHOTO YET!!
PLEASE LOOK AT THIS EXAMPLE:
X intercept: ( ), ( )
Y intercept: ( ), ( )
NOW LOOK. AT THE PHOTO PLEASE!!
Answer:
X-intercept: -10
Y-intercept: -45
(-10),(-45)
Step-by-step explanation:
Hop this helped, Have a Wonderful Day!!
Allan wanted to become a machine salesperson. He was offered a job that paid him $40,000 a year plus a commission of $300 for every machine he sells. If Allan made &50,800 last year, how many machine did he sell?
Answer:
36
Step-by-step explanation:
50800-30000=10800/300=36
:)
help please ASAP!!!!!
you can zoom in to see better
Answer:
true, false, and false
Step-by-step explanation:
Why is it important for mathematicians to graph functions? Select all that apply.
A. For them to determine if a function can be inverted.
B. For them to visualize the function.
C. For them to extrapolate beyond the known data.
D. For them to determine if the function can be graphed.
E. For them to determine characteristics of the function.
Answer:
e
Step-by-step explanation:
s
PLEASE HELP!!!! 50 POINTS!!!
Find the solution(s) of the following equation.
x^2 = 100/361
Choose all answers that apply:
a) x = -10/9
b) x = -1/6
c) x = 5/18
d) x = 5/9
e) none of the above
Answer:i think its b im not sure tho
Step-by-step explanation:
Answer: The answer is A) x= -10/19
45×(−10)×45 STEP explanation
Answer:
-20,250
Step-by-step explanation:
PEMDAS
Multiply left to right
45 * -10 * 45
45* -10
-450 * 45 =
-20,250
An integer is 15 more than 2 times another. If the product of the two integers is -27, then find the integers
Answer:
The required integers are x=3 and y= -9
Step-by-step explanation:
Let one the integers be x and y
An integer is 15 more than 2 times another: x=15+2y
product of the two integers is -27: x*y=27
[tex]x=15+2y ---eq(1)\\x*y=-27----eq(2)[/tex]
Solving both equations to find values of x and y
Putting value of x from equation 1 in equation 2
[tex](15+2y)*y=-27\\15y+2y^2=-27\\Rearranging:\\2y^2+15y-27=0[/tex]
This can be solved using quadratic formula:
[tex]$y=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$[/tex]
Putting values and finding factors
[tex]$y=\frac{-(15)\pm\sqrt{(15)^2-4(2)(-27)}}{2(2)}$\\$y=\frac{-(15)\pm\sqrt{225+216}}{4}$\\$y=\frac{-(15)\pm\sqrt{441}}{4}$\\$y=\frac{-(15)\pm21}{4}$\\$y=\frac{-(15)+21}{4} \ or \ y=\frac{-(15)-21}{4}$\\$y=\frac{6}{4} \ or \ y=\frac{-36}{4}$\\$y=\frac{3}{2} \ or \ y=-9$[/tex]
Since y is integer so, we consider only y= -9
The value of x will be:
[tex]x*y=-27\\x*(-9)=-27\\x=\frac{-27}{-9} \\x=3[/tex]
So, the value of x is x=3
The required integers are x=3 and y= -9
HELPPPPPPPPPPPPPPPPPPPPPPPPPPPP MEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE
Answer:
-0.4
Step-by-step explanation:
Answer:
Step-by-step explanation:
An airplane travels 5152 kilometers against the wind in 7 hours and 6552 kilometers with the wind in the same amount of time. What is the rate of the plane in still air and what is the rate of the wind?
What is 20 divided by 740 with remainder
Answer:
37 R0
Step-by-step explanation:
740/20=37, so there is no remainder.
I hope this helps you! Have a great day c:
Dividing 20 by 740 gives us remainder 20 and quotient 0.
To find the result of 20 divided by 740 with a remainder,
Perform the division and take note of the quotient and remainder.
20 ÷ 740 = 0 with a remainder of 20.
Division is a mathematical operation that involves splitting a number (the dividend) into equal parts,
with a divisor indicating how many parts we want to split it into.
The quotient is the number of equal parts, and the remainder is what's left after have split the dividend into as many equal parts as possible.
20 divided by 740, we are trying to find out how many times 740 can fit into 20.
Since 740 is much larger than 20, it cannot fit even once.
So, the quotient is 0, indicating that 0 whole units of 740 can fit into 20.
However, there is a remainder of 20.
The remainder represents the portion of 20 that cannot be evenly divided by 740.
It is what remains after we have divided the dividend by the divisor as many times as possible.
Therefore, 20 divided by 740 is 0 with a remainder of 20.
learn more about remainder here
brainly.com/question/29019179
#SPJ2
How many proportional relationships are shown
Answer:
2 I think thats the answer
Step-by-step explanation:
If a function is defined by the formula y=1/2x + 3 and its domain is given by the set {-4,0,8}, then which of the following sets gives the function's range?
Answer:
y = {1, 3, 7}
Step-by-step explanation:
Given
y = ½x + 3
Domain: {-4, 0, 8}
Required
Determine the range of the function
To do this, we simply substitute each value of the domain in the given expression
We start with the first
Substitute -4 for x in y = ½x + 3
y = ½ * -4 + 3
y = -2 + 3
y = 1
Then 0
Substitute 0 for x in y = ½x + 3
y = ½ * 0 + 3
y = 0 + 3
y = 3
Lastly, 8
Substitute 8 for x in y = ½x + 3
y = ½ * 8 + 3
y = 4 + 3
y = 7
Hence, the range of the function is:
y = {1, 3, 7}
Answer:1,3,7
Step-by-step explanation:
The function t= 21.55 cos (pi/6(m-7)) + 43.75 models the average high temperature in degrees Fahrenheit each month
Answer:
B - 8
Step-by-step explanation:
Answer:
answer is letter b 8
Step-by-step explanation:
Who wanna help me ???
25 points and brainlest
Answer:
2/5
Step-by-step explanation:
8/20=2/5
Help!! Please thanks
Answer:
i think you have chosen the right answer i don't really know its tricky for me
Step-by-step explanation:
AC=39 Find the length of AB
Answer:
AB = 12
Step-by-step explanation:
For a moving object, the force acting on the object varies directly with the object's acceleration. When a force of 28 N acts on a certain
object, the acceleration of the object is 7 m/s². If the acceleration of the object becomes 3 m/s2, what is the force?
Answer:
Step-by-step explanation:
F=ma
28=7m
m=28/7=4
F=4a
when a=3 m/s²
F=4×3=12 N
Work out (7×10^5) ÷ (2×10^2)
Give
your answer in standard form.
Answer:
3.5 X 10^3
Step-by-step explanation:
Write the equation of a line perpendicular to y=-5x that passes through the point (1,1) in slope intercept form. (This question is worth 2 points. One point for the correct slope and the second point is for the correct y intercept.)
Answer:
y= 1/5x + 0.8
Step-by-step explanation:
Hope this helps
How many times greater is the value of digit 1 in 21,648 than in 32,163?
Answer:
squirrel
Step-by-step explanation:
squirrel
Answer:
10
Step-by-step explanation:
Free brainliest timmmmmmme :)
What is 2+2?
A. 69
B. 420
C:666
D:21
PLEASE HELP WORTH 4 POINTS
Answer:
2+2=4
Step-by-step explanation:
lol tell me the subject and ill research and give u n answer
David has available 40 yards of fencing and wishes to enclose a rectangular area.
Answer:
5 units will be your width and 15 will be your length so it would look like side#1=5 side #2=15 side number3 is 5 and side number 4 is 15 assuming that side 1 and 3 are parallel.
Step-by-step explanation:
yes
What would be the answee
tell whether the transformation appears to be a rigid motion. explain
Answer:
If you turn it or flip it over or move it it is essentially the same shape. If you try to stretch the paper or fold it you change what the shape is so it is not a rigid motion. Since the two circles are not the same size then it is not a rigid motion
Suppose that a company has fixed costs of $23 per unit and variable costs $10 per unit when 13,500 units are produced. What are the fixed costs per unit when 10,000 units are produced?
answer
32632 answer hai bro
What is the meaning of the base of the function y= log(x)?
A. As y increases by 1, x increases by 10.
B. As y increases by 1, x increases by a factor of 10.
C. As y decreases by 1, x increases by a factor of 10.
D. As y decreases by 1, x increases by 10.