Answer:
£3446.05
Step-by-step explanation:
the interest for the first year
=£3200×2.5%
=£3200×2.5/100
=£80
the balance
=£3200+£80
=£3280
the interest for the second year
=£3280×2.5%
=£3280×2.5/100
=£82
the balance
=£3280+£82
=£3362
the interest for the third year
=£3362×2.5%
=£3362×2.5/100
=£84.05
the balance
=£3362+£84.05
=£3446.05
Scores at a local high school on the American College Testing (ACT) college entrance exam follow the normal distribution with a mean of 18 and a standard deviation of 8. A guidance counselor takes a random sample of 20 students and calculates the mean score, x¯.
(a) Calculate the mean and standard deviation of the sampling distribution of x¯.
(b) Interpret the standard deviation from part (a).
(c) Find the probability that a sample of 20 students has a mean score of 19.5 or more.
Answer:
a) The mean is 18 and the standard deviation is 1.79.
b) The interpretation is that the standard deviation of the sample means of groups of 20 students will be of 1.79, which is the sample error, which is different from the population standard deviation.
c) 0.2005 = 20.05% probability that a sample of 20 students has a mean score of 19.5 or more.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
Mean of 18 and a standard deviation of 8.
This means that [tex]\mu = 18, \sigma = 8[/tex]
Sample of 20:
This means that [tex]n = 20, s = \frac{8}{\sqrt{20}} = 1.79[/tex]
(a) Calculate the mean and standard deviation of the sampling distribution of x¯.
By the Central Limit Theorem, the mean is 18 and the standard deviation is 1.79.
(b) Interpret the standard deviation from part (a).
The interpretation is that the standard deviation of the sample means of groups of 20 students will be of 1.79, which is the sample error, which is different from the population standard deviation.
(c) Find the probability that a sample of 20 students has a mean score of 19.5 or more.
This is 1 subtracted by the pvalue of Z when X = 19.5. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{19.5 - 18}{1.79}[/tex]
[tex]Z = 0.84[/tex]
[tex]Z = 0.84[/tex] has a pvalue of 0.7995
1 - 0.7995 = 0.2005
0.2005 = 20.05% probability that a sample of 20 students has a mean score of 19.5 or more.
Please help me thanks
Answer:
11/13
Step-by-step explanation:
4 out of the 26 marbles are blue, meaning that the rest of the 22 marbles are not blue. (26-4=22)
This means that out of the total 26, the chance of not picking a blue marble are 22/26=11/13
GIVING BRAINLY need urgent help give evidence if you just answer for points you will be reported no biTLY LINKS
Answer:
1/5
Step-by-step explanation:
I hope this helps you
Answer:
1/5
Step-by-step explanation:
each X is divided by 5 to get the Y
Question 1
10 pts
The vertices of a triangle are P(4,7), Q(-1,7) and R(4,-5). What is the
perimeter of triangle PQR?
Answer:
30
Step-by-step explanation:
This problem can be done without the Distance Formula (which is a way to find the distance between any two points in the plane).
The attached image shows the points and segments joining them.
PQ = 5 because the points are on the same horizontal line, and you can count spaces between them (or subtract x-coordinates: 4 - (-1) = 5).
PR = 12 because the points are on the same vertical line; count spaces or subtract y-coordinates, 7 - (-5) = 12.
The triangle is a right triangle, so the Pythagorean Theorem can be used to find the length of the hypotenuse.
[tex](\text{leg})^2+(\text{leg})^2=(\text{hypotenuse})^2[/tex]
[tex](QR)^2=5^2+12^2=25+144=169\\QR=\sqrt{169}=13[/tex]
The perimeter of the triangle is 5 + 12 + 13 = 30
One of the authors and some statistician friends have an ongoing series of Euchre games that will stop when one of the two teams is deemed to be statistically significantly better than the other team. Euchre is a card game and each game results in a win for one team and a loss for the other. Only two teams are competing in this series, which we'l call team 1 and team 2.
Required:
a. Define the parameter of interest.
b. What are the null and alternative hypotheses if the goal is to determine if either team is statistically significantly better than the other at winning Euchre?
Answer:
Parameter of interest is the proportion of games won by a certain team.
H0 : p = 0.5
H1 : p ≠ 0.5
Step-by-step explanation:
Parameter refers to any statistical measure which is derived from the population data. Therefore, the parameter of interest in the scenario described above is the proportion of win or loss by a particular team. This could be either team A or team B.
Probability of either of either win or loss :
Proportion, p of win = 0.5
Null hypothesis ; H0 : p = 0.5
Alternative hypothesis ; H1 : p ≠ 0.5
subtract 8 from 10, then add n to the result
Answer:
(10-8) + n
Step-by-step explanation:
Good luck with your work!
Answer and Step-by-step explanation:
To subtract 8 from 10, it would look like this:
10 - 8.
Now, we add n to the result.
(10 - 8) + n
The question said not to simplify any part of this, so this is the expression.
(10 - 8) + n
#teamtrees #PAW (Plant And Water)
Which of the following could be points on the unit circle?
Answer:
A and D
Step-by-step explanation:
Unit circle is a circle described by the equation
x^2 + y^2 = 1
We can try each pair and check
A. [tex](\frac{6}{7})^2 + (\frac{\sqrt{13}}{7})^2 = \frac{36}{49} + \frac{13}{49} = \frac{49}{49} = 1[/tex]
B. [tex](\frac{4}{3})^2 + (\frac{4}{5})^2 > (\frac{4}{3})^2 > 1[/tex]
C. [tex](\frac{1}{3})^2 + (\frac{2}{3})^2 = \frac{1}{9} + \frac{4}{9} = \frac{5}{9} < 1[/tex]
D. [tex](\frac{5}{13})^2 + (\frac{12}{13})^2 = \frac{25}{169} + \frac{144}{169} = \frac{169}{169} = 1[/tex]
Find the length of the third side. If necessary, round to the nearest tenth.
15
9
The length of the third side is 12 units
How to determine the length of the third sideFrom the question, we have the following parameters that can be used in our computation:
A right triangle
This means that we can calculate the third length using the Pythagoras theorem
using the above as a guide, we have the following:
x = √(15² - 9²)
Evaluate the exression
x = 12
Hence, the third length is 12 units
Read more about right triangle at
https://brainly.com/question/2437195
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By increasing the down payment from 1,000 to 4,000, how does the total purchasing cost change?
Answer:
300%
Step-by-step explanation:
By increasing the down payment from 1,000 to 4,000, how does the total purchasing cost change?
If down payment is increased from 1000 to 4000
Icecrement = 4000-1000
Increment =3000
Percentage increase = 3000/1000×100
Percentage increase = 3000/10
Percentage increas=300%
Can someone help me?
Answer:
x = 12 efg = 132
Step-by-step explanation:
Hi,
4x = 48
x = 12
Which means...
m < EFG is
4x
4 (12) = 48
m < EFG is 48 degrees
I hope this helps :)
what is the height of the cone
Answer:
28
Yes Pog, You are Poggers
Please help, super confused!
Answer:
it is B
Step-by-step explanation:
anny has two boxes. One box contains 10 colored pencils, 4 of which are red and 6 of which are green. The other box contains 7 markers, 4 of which are red and 3 of which are blue. He chooses one colored pencil at random, and one marker at random. What is the probability of Manny choosing a green pencil and a red marker?
Answer:
12/35Step-by-step explanation:
p(green pencil) = 6/10 = 3/5p(red marker) = 4/7p(green pencil and red marker) = 3/5*4/7 = 12/35How many triangles can be made with sides measuring 7 cm, 4 cm, and 5 cm
Answer:
One triangle
Step-by-step explanation:
Since the sum of the shorter two sides is greater than the larger side.
Simplify each expression using the Order of Operations.
8-6 divided by 2+3 X 5
Answer:
8 - 6 ÷ 2 + 3 × 5
8 - 3 + 15
5 + 15
20
What is m<1
help thais would help
Answer:
it means it is less than one
Consider the following sample regressions for the linear, the quadratic, and the cubic models along with their respective R2 and adjusted R2.
Linear Quadratic Cubic
Intercept 29.83 29.35 26.88
x −0.04 0.16 2.11
x2 NA −0.02 −0.38
x3 NA NA 0.02
R2 0.001 0.001 0.008
Adjusted R2 −0.026 −0.053 −0.075
a. Predict y for x = 1 and 2 with each of the estimated models.
b. Select the most appropriate model.
1. Linear model
2. Cubic model
3. Quadratic model
Answer:
Kindly check explanation
Step-by-step explanation:
From the given information :
Linear model : y = - 0.04x + 29.83
Quadratic model : y = - 0.02x² + 0.16x + 29.35
Cubic model : y = 0.02x³ - 0.38x² + 2.11x + 26.88
Predicted y value for X = 1 ; X = 2
Linear model :
y = - 0.04(1) + 29.83 = 29.79
y = - 0.04(2) + 29.83 = 29.75
Quadratic model :
X = 1
y = - 0.02(1)^2 + 0.16(1) + 29.35 = 29.49
X = 2
y = - 0.02(2)^2 + 0.16(2) + 29.35 = 29.59
Cubic model :
X = 1
y = 0.02(1)^3 - 0.38(1)^2 + 2.11(1) + 26.88 = 28.63
X = 2
y = 0.02(2)^3 - 0.38(2)^3 + 2.11(2) + 26.88 = 28.22
Based on the R² value of the models given :
Linear ; R² = 0.001 ; R = sqrt(0.001) = 0.0316
Quadratic ; R² = 0.001 ; R = sqrt(0.001) = 0.0316
Cubic ; R² = 0.008 ; R = sqrt(0.008) = 0.089
Hence, the model which best fits the data is Cubic model.
Eric is a great skateboard fan. He visits a shop named SKATERS to
check some prices. At this shop you can buy a complete board. Or
you can buy a deck, a set of 4 wheels, a set of 2 trucks and a set of
hardware, and assemble your own board. The prices for the shop's
products are:
Answer:
minimum: 80 zeds
maximum: 137 zeds
Step-by-step explanation:
minimum price is where you choose all the cheapest options
lowest deck price is 40, lowest wheel set price is 14...
40+14+16+10
=40+30+10
=80
maximum price is where you choose all the most expensive options
highest deck is 65, highest price of wheels are 36, hardware 20
65+36+16+20
=65+72
=137
If there are 35 learners in this class, then determine the percentage of
learners who obtained a distinction (( > 80%).
Answer:
The question is an incomplete question
Find the value of the expression 4d ÷ c + 3 when c = 3 and d = 6
The value of the expression 4d ÷ c + 3 is 11.
What is Expression?A mathematical expression is a phrase that has a minimum of two numbers or variables and at least one mathematical operation. Let's examine the writing of expressions.
A mathematical operation such as subtraction, addition, multiplication, or division is used to combine terms into an expression.
Given:
4d ÷ c + 3
Now, for d= 6 and c= 3
we have
4d ÷ c + 3
= 4(6) / 3 + 3
= 4(2) + 3
= 8+ 3
= 11
Hence, the value of the expression is 11.
Learn more about expression here:
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A mayoral candidate in a large metropolitan area has hired you to take a poll to determine the proportion of registered voters who plan to vote for him. He would like you to report a 95% confidence interval with a margin of error no more than 0.04. Whiat is the smallest sample size that will produce an interval with these specifications?
Answer:
The smallest sample size that will produce an interval with these specifications is 601.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error is:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
He would like you to report a 95% confidence interval with a margin of error no more than 0.04. What is the smallest sample size that will produce an interval with these specifications?
We have to find n for which M = 0.04.
We dont know the true proportion, so we use [tex]\pi = 0.5[/tex], which is when the smallest sample size needed will have it's largest value.
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.04 = 1.96\sqrt{\frac{0.5*0.5}{n}}[/tex]
[tex]0.04\sqrt{n} = 1.96*0.5[/tex]
[tex]\sqrt{n} = \frac{1.96*0.5}{0.04}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*0.5}{0.04})^2[/tex]
[tex]n = 600.25[/tex]
Rounding up
The smallest sample size that will produce an interval with these specifications is 601.
what is the area of the triangle 16, 10, 8
Answer:
480
Step-by-step explanation:
(16x10x8) divided by 2 = 480
My teacher asked me 7 x 1/5 of 19, and I got immediately stumped. My brain is mush today.
Answer:
No lol that seems very confusing but was it 26.6?
Answer: 26.6
Step-by-step explanation:
7 times 1/5= 7/5
7/5 times 19= 26.6
I hope ti helps and may God bless you! have a nice day, bye!
pasagot po please...........
Answer:
1) ASA
2) SAS
3) SAS
4) SAS
5) SSS
please help asap i’ll give brainliest it's due in 30 min
The hypotenuse = √2 · legs
x = √2 · 5
x = 5√2
someone please answer this!!
Answer:
it 45
Step-by-step explanation:
u add 75 and 60 together which equals 135
then u subtract 135 from 180 and u get 45
From a group of 12 teachers, how many different committees can be formed
consisting four or five members?
Answer:
3=4÷12
3groups with 4 members (teachers)and we cannot make groups with 5 members
2 5/6+ 3 2/5 in simplest form.
Answer:
17/6 + 17/5
Step-by-step explanation:
Solve the simultaneous equations
2x - 3y = 12
3x + 4y = 1
What am I doing wrong here?
Answer:
3
Step-by-step explanation:
2×-3y = 12 ( multiply whit 4)
3x + 4y =1 (multiply whit 3 )
8x -12y =48
9X+ 12y = 3
if you add this equations
17X =51
X= 51 / 17
x=3
There's your answer buddy!
Find the erea of the trapezoid.
show work for brainliest
Answer:
the area of the trapezoid is 32
Step-by-step explanation:
a (base)2
b (Base)6
h (height)8