Answer:
a) 0.105 = 10.5% probability that it will not be discovered if it has an emergency locator.
b) 0.522 = 52.2% probability that it will be discovered if it does not have an emergency locator.
c) 0.064 = 6.4% probability that 7 of them are discovered.
Step-by-step explanation:
For itens a and b, we use conditional probability.
For item c, we use the binomial distribution along with the conditional probability.
Conditional Probability
We use the conditional probability formula to solve this question. It is
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]
In which
P(B|A) is the probability of event B happening, given that A happened.
[tex]P(A \cap B)[/tex] is the probability of both A and B happening.
P(A) is the probability of A happening.
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.
a) If it has an emergency locator, what is the probability that it will not be discovered?
Event A: Has an emergency locator
Event B: Not located.
Probability of having an emergency locator:
66% of 72%(Are discovered).
20% of 100 - 72 = 28%(not discovered). So
[tex]P(A) = 0.66*0.72 + 0.2*0.28 = 0.5312[/tex]
Probability of having an emergency locator and not being discovered:
20% of 28%. So
[tex]P(A cap B) = 0.2*0.28 = 0.056[/tex]
Probability:
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.056}{0.5312} = 0.105[/tex]
0.105 = 10.5% probability that it will not be discovered if it has an emergency locator.
b) If it does not have an emergency locator, what is the probability that it will be discovered?
Probability of not having an emergency locator:
0.5312 of having. So
[tex]P(A) = 1 - 0.5312 = 0.4688[/tex]
Probability of not having an emergency locator and being discovered:
34% of 72%. So
[tex]P(A \cap B) = 0.34*0.72 = 0.2448[/tex]
Probability:
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.2448}{0.4688} = 0.522[/tex]
0.522 = 52.2% probability that it will be discovered if it does not have an emergency locator.
c) If we consider 10 light aircraft that disappeared in flight with an emergency recorder, what is the probability that 7 of them are discovered?
p is the probability of being discovered with the emergency recorder:
0.5312 probability of having the emergency recorder.
Probability of having the emergency recorder and being located:
66% of 72%. So
[tex]P(A \cap B) = 0.66*0.72 = 0.4752[/tex]
Probability of being discovered, given that it has the emergency recorder:
[tex]p = P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.4752}{0.5312} = 0.8946[/tex]
This question asks for P(X = 7) when [tex]n = 10[/tex]. So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 7) = C_{10,7}.(0.8946)^{7}.(0.1054)^{3} = 0.064[/tex]
0.064 = 6.4% probability that 7 of them are discovered.
A chemist examines 17 sedimentary samples for lead concentration. The mean lead concentration for the sample data is 0.268 cc/cubic meter with a standard deviation of 0.069. Determine the 80% confidence interval for the population mean lead concentration. Assume the population is approximately normal. Step 1 of 2 : Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Answer:
The critical value that should be used in constructing the confidence interval is T = 1.337.
The 80% confidence interval for the population mean lead concentration is between 0.246 and 0.29 cc/cubic meter.
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 17 - 1 = 16
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 16 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.8}{2} = 0.9[/tex]. So we have T = 1.337, which is the crical value.
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 1.337\frac{0.069}{\sqrt{17}} = 0.022[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 0.268 - 0.022 = 0.246 cc/cubic meter
The upper end of the interval is the sample mean added to M. So it is 0.268 + 0.022 = 0.29 cc/cubic meter
The 80% confidence interval for the population mean lead concentration is between 0.246 and 0.29 cc/cubic meter
after 4 new students joined a class,the class had 32 students.Which equation can be used to find n,the number of students in the class before the 4 new students joined
The enrolment of our school is 800. If 35 % are girls
a. What fraction are girls?
b. What fraction are boys?
Answer:
a 7/20. B 13/20
Step-by-step explanation:
800 X 35% = 280
280/800=7/20
Answer:
a. 280/800 (or 7/20 simplified)
b. 520/800 (or 13/20 simplified)
Step-by-step explanation:
a. 800 × 0.35 = 280
Fraction of girls = total girls/total enrollment = 280/800 (or 7/20 simplified)
b. Total boys = Total enrollment - total girls = 800 - 280 = 520
Fraction of boys = total boys/total enrollment = 520/800 (or 13/20 simplified)
what is the mean of this data set? 11,12,16,11,15,19,13
Answer:
13.857142
Step-by-step explanation:
Took a lot of math.
Complete the proof.
Prove: AUWX - AUW
A)
AAS
B)
ASA
C)HL
D)
SAS
Answer:D) SAS
Step-by-step explanation:
USA test prep
I dunno this answer... pwease help... if you're smart
Answer:
H: (2, 14)
O: (4,15)
U: (6,14)
S: (2,10)
E: (6,10)
Step-by-step explanation:
the image on the grid is after doin x- 1 and y-7
to get the preimage do the inverse , x + 1 , y + 7
note- a coordinate is written as (x,y)
so, add 1 to all the x's and 7 to all the y's on the coordinates on the grid!
and sorry for asking but, if this is right could i please get a thanks & brainliest recently a moderator deleted ALL my answers (over 400 answers) causing me to lose over 3k points so id appreciate it alot thanks xoxo
Which one is the answer
Leanna is making a craft and needs 12 yards of ribbon. If 2 yards of ribbon cost $1.25, how much will 12 yards cost?
Answer:
$7.50
Step-by-step explanation:
2 yd= 1.25
we have 12 yd so 12/2= 6
6*1.25= 7.50
Help me please, Due Today.
Answer:
D,F and E,G are parallel
Step-by-step explanation:
slove with cool mind
Fernando had 2 children. Each of their children had 2 children, and each of these
He had 2 children. How many grandchildren did Fernando have?
Answer:
4 grand children
Step-by-step explanation:
Answer:
6 grandkids
Step-by-step explanation:
fernando has 2 kids and each had their own sets of kids so
1 fernando's kid 1 fernando's kid
2 grandchildren 2 grandchildren
=4 grandchildren in total
you said the grandchildren had kids as well so
2+4=6
What is the volume?
1 mm
1 mm
1 m
Answer:
volume equals length times width times height
Step-by-step explanation:
PLEASE SOMEONE HELP ME WITH THIS PROBLEM
Answer:
1.28
2. -3.5
3.-10.5
Step-by-step explanation:
1.-0.0035 · 12000+70= 28
2. -0.0035 ·21000+70=-3.5
3. -0.0035 ·23000+70=-10.5
I hope this helps
Why is the y - intercept of the function f(x) =4-5x
Answer: (0,4)
Step-by-step explanation:
Simplify
-3(2.5-k)+0.5(7+8k)
Answer:
-7•5+3k+3•5+4k
-7•5+3•5+4k+3k
-4+7k
2) In a random survey of 500 women, 315 said they would rather be poor and thin than rich and fat; in a random survey of 400 men, 220 said they would rather be poor and thin than rich and fat. Is there sufficient evidence to show that the proportion of women who would rather be poor and thin than rich and fat is greater than the proportion of men who would rather be poor and thin than rich and fat
Answer:
Since the calculated value of Z= 0.242887 is less than Z (0.05) = 1.645 and falls in the critical region we reject the null hypothesis and conclude that there is not sufficient evidence to show that the proportion of women who would rather be poor and thin than rich and fat is greater than the proportion of men who would rather be poor and thin than rich and fat.
Step-by-step explanation:
Here
p1= proportion of women who would rather be poor and thin than rich and fat
p1= 315/500= 0.63
p2= proportion of men who would rather be poor and thin than rich and fat
p2= 220/400= 0.55
1) Formulate the hypothesis as
H0: p1>p2 against the claim Ha: p1 ≤ p2
2) Choose the significance level ∝0.05
3) The test Statistic under H0 , is
Z= p1^ - p2^ / sqrt( pc^qc^( 1/n1 + 1/n2))
pc^= an estimate of the common proportion
pc ^ = n1p1^ + n2p2^/ n1+n2
4) The critical region is Z≤ Z (0.05) = 1.645
5) Calculations
pc^ = 315+ 220/ 500+400= 535/900
pc^= 0.5944
and qc^= 1-0.5944= 0.4055
Thus
Z = 0.63-0.55/ sqrt ( 0.5944*0.4055( 1/500+ 1/400))
Z= 0.08/ sqrt (0.24108 (900/2000))
Z= 0.08/√0.10849
Z= 0.242887
Conclusion :
Since the calculated value of Z= 0.242887 is less than Z (0.05) = 1.645 and falls in the critical region we reject the null hypothesis and conclude that there is not sufficient evidence to show that the proportion of women who would rather be poor and thin than rich and fat is greater than the proportion of men who would rather be poor and thin than rich and fat.
The value of a boat is depreciating at a rate of 7% per year. In 2006, the boat was worth $17,300. Find the value of the boat in 2011. Enter the exponential decay function for this situation.
The exponential decay function is y = .
In 2011 the boat will be worth $ .
Answer:
Step-by-step explanation:
[tex]V=Ar^t\\ \\ V=17300((100-7)/100)^t\\ V=17300(0.93)^{(y-2006)}\\ V(2011)=17300(0.93)^{(2012-2006)}=\$ 11192.29[/tex]
I WILL MARK BRAINLIST, HELP PLEASE
Answer:
D
Step-by-step explanation:
hope it helped you in any way
what is x 4(x-2)=2(x+1)
X = 5
Isolate the variable by dividing each side by factors that don't contain the variable.
Answer:
X=5
4(x-2)=2(x+1)
4x-8=2x+2
+8 +8
4x=2x+10
-2x -2x
2x=10
2x 2x
X=5
26 points!!
feet. What is the volume of the box?
A box has a length of 4 feet, a width of 24 feet, and a height of 1
O A 17 cubic feet
OB. 8 cubic feet
O C. 8 - cubic feet
OD. 35 cubic feet
Answer:
yes
Step-by-step explanation:
what is the answer?
plz help
Answer:-516
Step-by-step explanation:
Answers:
The simplified expression is -4x The value is -516===========================================
Explanation:
To simplify this, we combine the coefficients. This works because all of the terms have 'x' in them and nothing else (they are all like terms). We can think of this problem as trying to evaluate -12+14-6. This simplifies to -4
So -12x+14x-6x simplifies to -4x
Afterward, we replace x with 129 to get
-4x = -4*129 = -516
Find a. Give your answer in
the simplest form.
[?]
a
zva
d
а
45
30
b
с
Answer:
a=7
Step-by-step explanation:
7(sq rt 2)=(sq rt 98)
sin 45=a/(sq rt 98)
0.7071=a/(sq rt 98)
a=0.7071(sq rt 98)
a=7
Approximate 589.57 to the nearest whole number..
Answer:
590.00
Step-by-step explanation:
Im guessing SORRY
Which of the following transformations shows that figure C is congruent to figure C'?A.reflection in the x-axis
B.rotation 90 counterclockwise about the origin
C.rotation 180 counterclockwise about the origin
D.rotation 270 counterclockwise about the origin
Answer: D.rotation 270 counterclockwise about the origin
Step-by-step explanation:
Simplify (1/2)^4
1/10
1/8
1/4
Answer:
1/8
Step-by-step explanation:
[tex] \bigg( \frac{1}{2} \bigg)^{4} = \\ \\ = \frac{1}{8} [/tex]
NEED HELP ASAP!!!Of all the students who tried out for volleyball, 83% made the team what fraction of the students who tried out did NOT make the team?
Answers
4/5
1/5
3/4
1/3
Answer:I think it’s 1/5 but if u have another attemp and it’s wrong somehow do 1/3
Step-by-step explanation:
Answer:
3/4 or 1/3
Step-by-step explanation:
The probability that it will rain tomorrow is 0.65
What is the probability that it will not rain tomorrow?
Answer:
.35%
Step-by-step explanation:
100% - .65% = .35%
and sorry for asking but, if this is right could i please get a thanks & brainliest recently a moderator deleted ALL my answers (over 400 answers) causing me to lose over 3k points so id appreciate it alot thanks xoxo
help please will mark brainliest
Answer:
I think 1, 4, 5 and 7
Step-by-step explanation:
The ratio of boys to girls is 2 to 3. There are 10 boys. How many girls are in the club?
Answer:
15 girls.
Step-by-step explanation:
Hope this helps!
Answer:
15 girls
Step-by-step explanation:
2:3 ratio
If you know the amount of boys, then 2x=10, x=5
Now you know that the scale factor is 5
So, multiply 5*3 to get the amount of girls
There are 4 games at the carnival Kevin played all the games in 24 minutes. How many minutes did he spend at each game if he spent an equal amount of time at each?
Answer:
6 minutes at each game
Step-by-step explanation:
24 minutes divided by 4 games, if he spends and equal amount of time at each game it would be 24/4=6
Answer:
6
Step-by-step explanation:
24/4=6
9a + 18c. What is the value of the expression when a = −5 and c = −1?