Answer:
P(X < 4) = 0.5
Step-by-step explanation:
For each question, there are only two possible outcomes. Either it is answered correctly, or it is not. The probability of a question being answered correctly is independent of any other question. This means that we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
In this question, we have that:
[tex]n = 7, p = 0.5[/tex]
Find the probability that the number of correct answers is fewer than 4:
This is
[tex]P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3)[/tex]
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{7,0}.(0.5)^{0}.(0.5)^{7} = 0.0078[/tex]
[tex]P(X = 1) = C_{7,1}.(0.5)^{1}.(0.5)^{6} = 0.0547[/tex]
[tex]P(X = 2) = C_{7,2}.(0.5)^{2}.(0.5)^{5} = 0.1641[/tex]
[tex]P(X = 3) = C_{7,3}.(0.5)^{3}.(0.5)^{4} = 0.2734[/tex]
[tex]P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) = 0.0078 + 0.0547 + 0.1641 + 0.2734 = 0.5[/tex]
So
P(X < 4) = 0.5
the sales price for a bicycle $315. the original price was first discounted by 5o% and then discounted by 10%. find the original price of the bicycle
Answer:
?× ( 1 − 50/ 100 ) × ( 1 − 10/ 100 ) = $ 315 ? = $ 315 /( .5 ) ( .9 ) = $ 700
Step-by-step explanation:
I need help with this??
Select both the 2nd and 4th options!
Working together, two pumps can drain a certain pool in 6 hours. If it takes the older pump 15 hours to drain the pool by itself, how pump to drain the pool on its own?
Answer:
10
Step-by-step explanation:
Rate of drainage for pump A and B = [1 pool drained]/[6 hours]
Rate of drainage for pump A (older pump) = [1 pool drained]/[15 hours]
Rate for pump B (newer pump) = [1 pool drained]/[t hours]
Thus, adding the rate of drainage of A and B,
1/t + 1/15 = 1/6
t=10
HELP HELP HELP HELP HELP HELP HELP
Answer:
Hi,
In a square, all sides are equal.
The area is obtained by multiplying one side by another side.
So, A = L^2
A = Area
L = length of a side
24ft^2 = L^2
L = square root(24) = 4.9
L = 4.9
We can say x^2 = 24
And the length of one side is therefore 4.9
people of brainly i need help what is 32.70 divided by 5
Answer:
6.54
Step-by-step explanation:
32.70/5
Answer:
6.54
Step-by-step explanation:
32.7/5=6.54
While abroad in Cairo, Egypt, you want to visit three other cities: Damanhur, Alexandria, and Suez. The following table details the costs of traveling to and from each city. All costs are given in Egyptian pounds (EGP).
Origin and Destination
Cost (EGP)
Cairo to Damanhur
153
Cairo to Alexandria
171
Cairo to Suez
130
Damanhur to Cairo
143
Damanhur to Alexandria
174
Damanhur to Suez
182
Alexandria to Cairo
167
Alexandria to Damanhur
192
Alexandria to Suez
144
Suez to Cairo
133
Suez to Damanhur
156
Suez to Aledandria
156
What is the cost of the most efficient route? You may visit the cities in any order, but you must begin and end in Cairo.
a.
EGP 589
b.
EGP 604
c.
EGP 614
d.
EGP 621
The answer is B) EGP 604
Answer:
b
Step-by-step explanation:
I NEED HELP NOW PLZZ!!
Answer:
option C is the correct option!!
Can someone PLEASE help me!
50 POINTSSS PLSSS HELP I AM UNSURE WHAT TO DO
PLSSSS HELP! 11^9–11^8+11^7 is divisible by 3 and 37.
Answer:
Step-by-step explanation: 11^9 -11^8 + 11^7 = 2163075981
2163075981/3 = 721025327
2163075981/37 = 58461513
Yes it is divisible by both 3 and 37
whoever gets this correct first gets brainlest !!!
Answer:
9.9
Step-by-step explanation:
The quadrilaterals are similar by a factor of 3.
Find the perimeter of a rectangle with a width of (x-3) and length of 4x.
Answer: 10x-6
Step-by-step explanation: perimeter is adding all the sides outside of the shape
Which expression is equivalent to 3y+4+y
help me please. need it asap
Answer:
X=-1
Y=-8
hope this helps!
Step-by-step explanation:
Amelia receives two dozens roses for her birthday. 18 of the roses are pink what percent of the roses are pink
18/24 = pink roses... 75% of the roses are pink.
Express 2431 in simplest radical form.
Answer:
I am expecting that 24.31 I am guessing
Image plz helppppppp
Answer:
239,940
Step-by-step explanation:
v(t) = 279,000(0.68)[tex]^{t}[/tex]
279,000 x 0.68 = 239,940
At Davis's Hat Store around the block, they have a total of 300 hats in the store. 14% of the hats are white.
How many of the hats in the store are white?
Answer:
42.
Step-by-step explanation:
14% of 300 is 42.
hope this helped
julio has $10 in a bank account. each week he earns $125. let x represent the number of weeks and f(x) represent the account balance,
Answer:
f(x) =10+125x
Step-by-step explanation:
Given data
Account Blance= $10
Weekly earning= $125
Let x be the number of weeks
and the account Balance after x weeks be f(x)
Hence the expression for the account balance is
f(x) =10+125x
Which of the following is equivalent?
Answer:
0.4
Step-by-step explanation:
Yeetyettyeteheheyehe
write each ratio in the simplest form:
12 feet to 9 yards
Answer:
9 ft 3.00 yd
Step-by-step explanation:
Answer:
4:3
Step-by-step explanation:
divide 12 by 3 to get 4 and dive 9 by 3 to get 3
PLEASE ASAP HELP GIVING BRAINLIEST AND DOUBLE POINTS!!
Step-by-step explanation:
Given
Area of the cube (A) = 64 cm²
Now
The volume of the cube (V)
[tex]v \: = {a}^{ \frac{3}{2} } \\ v \: = 64 ^{ \frac{3}{2} } \\ v = 8 ^{ \frac{3 \times 2}{2} } \\ v \: = {8}^{3} \\ v = 512cm ^{3} [/tex]
Hope it will help :)❤
Answer:
512 cm³Step-by-step explanation:
Let us understand the letters in the formula first. The rest is really quite simple.
V = volume
A = area
Let's substitute the known area in for A
V = 64^3/2
Solve for V
64^3/2 = 512
V = 512
Hence, the volume of the cube is 512 cm³
4.40
.63
4.79
.13
2.07
.77
9.28
.47
6.93
.20
Answer:
can you do elaborate more please?
Help for brainliest
Answer:
Rotation of 180 degrees, either direction
Dilation, making it smaller by some factor(we aren't given measurements so we cannot be exact)
Then move the figure to the right and then move the figure up
Step-by-step explanation:
Find the median of 6,2,0,1,1,2,3,2,0,2,3,4,2,3,5
Answer:
2
Step-by-step explanation:
The median is the middle number when the numbers are lined up from least to greatest or greatest to least.
First, the numbers must be lined up from least to greatest.
0, 0, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 4, 5, 6
Then, find the middle number.
The middle number is 2.
Which number is a multiple of 4?
A. 26
B. 32
C. 14
D. 22
Answer:
B) 32
Step-by-step explanation:
8 x 4 = 32
The fox population in a certain region has a relative growth rate of 5 percent per year. It is estimated that
the population in the year 2000 was 29100.
a) Find a function that models the population t years after 2000 (t = 0 for 2000).
P(t)
b) Use the function from part (a) to estimate the fox population in the year 2008. Round to the
nearest fox.
foxes
Answer:
A: P(t)=29100e^(.05t)
B: ≈43412
Step-by-step explanation:
A: The formula A=Pe^(rt) can be used. Initial value of 29100, e is the exponential constant, the rate is 5% which can be seen as 5/100, and t=time
B: Use the equation you created and substitute 8 for t since the years of difference between 2008-2000 is 8 years
29100e^(.05(8)) ≈ 43412.0987014
Rounded to the nearest fox is ≈43412
someone helppp! This is due the day after tomorrow!!
Step-by-step explanation:
Given
(2x + 3 )² - (2x + 3) (x - 5)
= 4x² + 6x + 9 - ( 2x (x - 5) + 3(x - 5 ))
= 4x² + 6x + 9 - ( 2x² - 10x + 3x - 15 )
= 4x² + 6x + 9 - 2x² + 10x - 3x + 15
= 2x² + 13x + 24
Hope it will help :)
7. Which of the following is a linear inequality in two
variables?
А. За - 4b = 5
C. 3x < 21
B. 7x + 3 < 12
D. 11 + 3t 2s
Answer:
c
Step-by-step explanation:
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DC kh0a74apyrYDLpsuro7rs
Which of the following are solutions to the equation below?
Check all that apply
x-2x - 24=0
A -6
B-24
C 4
D 6
E. -4
The price of a CD player was reduced from $80 to $52. What was the percent decrease in the price of the CD player?
Answer:
35%
Step-by-step explanation:
The cd players price decresed by 35%
The percentage decrease is given by the equation P = 35 %
What is Percentage Error?
The difference between an exact value and an approximation to it is the approximation error in a data value. Either an absolute error or a relative error might be used to describe this error.
Percentage error is the difference between the measured value and the true value , as a percentage of the true value
Percentage Error = [ ( | Measured Value - True Value | ) / True Value ]x 100
Given data ,
Let the percentage decrease be P
Let the original cost of the CD player be A = $ 80
Let the reduced price of the CD player be B = $ 52
Now , the equation will be
Percentage Decrease = [ ( | Measured Value - True Value | ) / True Value ]x 100
Substituting the values in the equation , we get
Percentage decrease P = [ ( 80 - 52 ) / 80 ] x 100
On simplifying the equation , we get
Percentage decrease P = ( 28/80 ) x 100
Percentage decrease P = 0.35 x 100
Percentage decrease P = 35 %
Therefore , the value of P is 35 %
Hence , the percentage decrease is 35 %
To learn more about percentage error click :
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