Answer:
t = -1.54.
Step-by-step explanation:
The test statistic is:
[tex]t = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
H0:μ=54.5
This means that [tex]\mu = 54.5[/tex]
Your sample consists of 48 subjects, with a mean of 54.1 and standard deviation of 1.8.
This means, respectively, that [tex]n = 48, \mu = 54.1, \sigma = 1.8[/tex]
Test statistic
[tex]t = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]t = \frac{54.1 - 54.5}{\frac{1.8}{\sqrt{48}}}[/tex]
[tex]t = -1.54[/tex]
The test statistic is t = -1.54.
Scores of an IQ test have a bell-shaped distribution with a mean of and a standard deviation of . Use the empirical rule to determine the following. (a) What percentage of people has an IQ score between and ? (b) What percentage of people has an IQ score less than or greater than ? (c) What percentage of people has an IQ score greater than ?
Complete question is;
Scores of an IQ test have a bell-shaped distribution with a mean of 100 and a standard deviation of 13. Use the empirical rule to determine the following.
(a) What percentage of people has an IQ score between 87 and 113?
(b) What percentage of people has an IQ score less than 74 or greater than 126?
(c) What percentage of people has an IQ score greater than 139?
Answer:
A) 68% of the people had an IQ score between 87 and 113
B) 5% of the people had IQ scores less than 74 and greater than 126.
C) 0.15% had an IQ score greater than 139
Step-by-step explanation:
We are given;
Mean; x¯ = 100
Standard deviation; σ = 13
According to the empirical rule in statistics;
>> 68% of the data lies within one standard deviation of the mean
>> 95% of the data lies within two standard deviations of the mean
>> 99.7% of the data lies within three standard deviations
A) We want to find the percentage of people with an IQ score between 87 and 113.
Within one standard deviation, we have;
x¯ ± σ
>> (100 - 13), (100 + 13)
>> (87, 113) which is the range we are looking for.
Thus, 68% of the people had an IQ score between 87 and 113
B) we want to find percentage of people has an IQ score less than 74 or greater than 126.
Let's first find those who had between 74 and 126.
Let's use two standard deviations within the mean.
x¯ ± 2σ
>> (100 - (2×13)), (100 + (2×13))
>> (74, 126) which is the range we are looking for.
So percentage that have IQ scores between 74 and 126 is 95%
Thus;
Percentage of those who had less than 74 and greater than 126 is;
P = 1 - 95%
P = 5%
C) we want to find the percentage of people that had an IQ score greater than 139.
Let's use the z-score formula;
z = (x¯ - μ)/σ
z = (139 - 100)/13
z = 39/13
z = 3
This means it is 3 standard deviations above the mean.
Thus;
Since it's one side outside the mean, then;
Percentage of people with an IQ score greater than 139 = (1 - 99.7%)/2 = 0.3%/2 = 0.15%
Which equation represents a circle that has a center at and a radius of 5?
what are the options?
Please help me.
1. Reflect triangle PQR over the y-axis. Then, describe what happened to each of the coordinates.
2. Reflect your new triangle P’Q’R over the x-axis. Describe what happened to each of the coordinates
Answer:
make dot in the 2,2 8,2 and 5,7 and join the dots
round your answer to two decimal places. x + 1/x+3=3/5
Answer:
X=2
Step-by-step explanation:
Please mark answer as brainliest
HELP PLS!! according to the rational root theorem, -2/5 is a potential rational root of which function?
Answer:
hi
Step-by-step explanation:
According to the Rational Roots Theorem, the possible rational roots are all the factors of the constant term expressed over the factors of the leading coefficient of the polynomial function. The reason is that the numerator of this rational root is a factor of 4 and the denominator is a factor of 25.
DOES IT HELP?!
Answer: D
Step-by-step explanation: Got it right
need help geometry question central angles and arcs !!! PLS HELP
Answer:
150°
Step-by-step explanation:
35 + 120 + 55 = 210
360 - 210 = 150
In ΔEFG, the measure of ∠G=90°, FG = 15 feet, and GE = 87 feet. Find the measure of ∠F to the nearest degree
Answer:
80
Step-by-step explanation:
delta math
What is the acceleration of a 4.5 kg mass when there is a net force of 18 N on
it? Please show me the equation if you know.
Answer:
Step-by-step explanation:
a=F/m
a=18/4.5
a=4 m/s/s
hope this helped! :D
I am confused I got 9.7 but I am not sure? Any help out there.
Answer:
Im not sure If your suppose to calculate the whole area but for FGH Its 9
Step-by-step explanation:
Find the Surface Area. I need the answer fast.
Answer:
1615
Step-by-step explanation:
Area of triangle is: A= B•H•1/2
Area of square is A= L•W
39•17•1/2= 331.5
331.5•4= 1326
17•17= 289
Add the square area to the area of the triangles
289+ 1326= 1615
hope this helps chu <3
Answer:
663
Step-by-step explanation:
Since we are finding the area we multiply Length times Width which is a way of finding formal. L x W so the Length is 17 and Width is 39 so
17 x 39 = 663. So the area is 663
I want a expert or someone that can tell me this %100 I’m offering a brainalist + 20 points
Answer:
The answer is A
Step-by-step explanation:
Supplementary angles are angles which add up to 180°
∠1 and ∠3 add up to 180°, so they are supplementary.
you invested money in two funds. last year, the first fund paid a dividend of 9% and the second a dividend of 3%, and you receive a total of $921. This year, the first fund paid a 10% dividend and the second only 1%, and you received a total of $846. How much money did you invest in each fund?
Answer:
x= $ 7100 investment in first fund
10x+y=84600 substitute the value of x
10*7100+y=84600
y=84600-71000
y= $ 13600 investment in second fund.
Step-by-step explanation:
What value of a satisfies the following equation?
-2(a + 3) = -4a + 32
Answer:
a = 19
Step-by-step explanation:
-2(a + 3) = -4a + 32
-2a - 6 = -4a +32
+2a +2a
-6 = -2a + 32
-32 -32
-38 = -2a
divide by -2
a = 19
Answer:
a=19
Step-by-step explanation:
-2(a+3) = -4a + 32
-2a - 6 = -4a + 32(Group like terms)
-2a+4a=32+6
2a=38(Divide both sides by 2)
a=19
Math help!
Please only answer if you know the answer, the comment section is right below. Please don't waste my points!
Also, please show all of your work, you are trying to help me better understand the concept, not just give me the answer.
The image is down below. Show work! Thanks!
Answer: 1675 Ft. = Distance from
fire to the windmill.
Step-by-step explanation:
tan8 = 140/X1.
X1 = 140/tan8 = 996.2 Ft.
tan3 = 140/(996+X2)
996+X2 = 140/tan3 = 2671
X2 = 2671-996 = 1675 Ft. = Distance from
fire to windmill.
jim began to bike a 173 mile bicycle trip to build up stamina for a for a triathlete competition. Unfortunately, his bicycle chain broke, so he finished the trip walking. The whole trip took 5 hours. If Jim walks at a rate of 4 miles per hour and rides at the rate of 38 miles per hour , find the amount of time he spent on the bicycle
Answer
3.5 hours
Step-by-step explanation:
Let us represent
The time spent walking as x
The time spent riding as y
Jim began a 146-mile bicycle trip to build up stamina for a triathlete competition. Unfortunately, his bicycle chain broke, so he finished the trip walking. The whole trip took 5 hours.
Hence:
x + y = 5.... Equation 1
x = 5 - y
If Jim walks at a rate of 4 miles per hour and rides at 40 miles per hour,
The formula for Distance = Speed × time. Hence,
4 × x + 40 × y = 146 miles
4x + 40y = 146.... Equation 2
We substitute 5 - y for x in Equation 2
4(5 - y) + 40y = 146
20 - 4y + 40y = 146
Subtract 20 from both sides
20 - 20 - 4y + 40y = 146 - 20
- 4y + 40y = 146 - 20
36y = 126
y = 126/36
y = 3.5 hours
Since the time he spent raiding his bicycle is represented by "y", the amount of time he spent on the bicycle is 3.5 hours
I think this is right I had this question I think it was the same one I dont know tho
Expand (2+x)^3 using binomial theorem
Step-by-step explanation:
= 2³ + x ³ + 3(2)²x + 3(2)x²
= 8 + x³ + 12x + 6x²
= x³ + 6 x² + 12 x + 8
Determine whether the situation calls for a survey, an observational study, or an experiment. You want to find out if a new drug can help decrease the symptoms of migraine headaches.
experiment
observational study
survey
observational study is the wrong answer
Answer:
Experiment.
Step-by-step explanation:
It helps you determine the effect of the medication in a controlled environment with variables and controls.
1+1a+1-1=1 plssssssssssss telllllllll meeeeeee
Answer:
a=0
Step-by-step explanation:
first, find the coefficient of 1 (doenst have to be written)
1+a+1-1=1
remove the opposites
1+a=1
cancel equal terms
a=0
You invest $2,000 in an investment that pays an annual interest rate of 7.5% with monthly compounding. How many months will it take for your investment to be worth $3,500
Answer:
10 years
step-by-step explanation:
First, divide 7.5 by 100, you should get 0.075, then multiply 0.075 by 2000, you should get 150, thats how much interest he gains each year, now subtract 2000 from 3500 to see how much he needs to get to 3500, you should get 1500, now divide 1500 by 150, you should get 10, which is how many years he will need to get to 3500 from 2000
The confidence interval based on the two-sample design is wider because there is considerable variation in mileage between the cars. The confidence interval based on the paired design is wider because there is little variation in mileage between the cars. The confidence interval based on the two-sample design is wider because there is little variation in mileage between the cars. The confidence interval based on the paired design is wider because there is considerable variation in mileage between the cars.
Answer:
The confidence interval based on the paired design is wider because there is little variation in mileage between the cars.
Step-by-step explanation:
The sample size randomly collected is matched sample and since the confidence interval is based on the paired design is large and wide. There is small variation between the mileage of the two cars indicating the cars have mileage based on the fuel.
In the linear equation y = 4x + 2, the value 2 represents which of the following?
A:The slope of the line
B: The y- coordinate of the y-intercept
C: The x-coordinate of the y-intercept
D: The quadrant in which the line lies
HELP PLEASE DO NOT PUT A LINK
Answer:
No
No
Yes
Yes
No
Step-by-step explanation:
HELP ME I BEED THIS DONE!
18 A bank charges a $ 10 fee to open an
account. Which of the following equations
best represents the total amount in the
account, m, when starting with d, dollars?
A. m = d + 10
B. m = d - 10
C. m - 10 = d
D. m + d = 10
what is the value of x?
Step-by-step explanation:
Continuation of the answer
4x=180 degrees
X=180/4=45 degrees.
In 2005, there were 560 students in the eighth grade class at Maddison Middle School. In 2006, there were 590 students and in 2007 there were 616 students. What is the percent of increase from 2005 to 2007?
Answer:
5.357142857
Step-by-step explanation:
Semira’s puppy weighs 12.4 pounds and is growing at a rate of 0.8 pound per week. Cedric’s puppy weighs 9.2 pounds and is growing at a rate of 1.2 pounds per week. Let x represent the time in weeks and y represent the weight of the puppy in pounds. Which system of equations can Semira and Cedric use to determine after how many weeks their puppies will weigh the same?
{y=0.8x+12.4
{y=1.2x+9.2
{y=12.4x+0.8
{y=9.2x+1.2
{y=0.8x+1.2
{y=12.4x+9.2
{y=1.2x+0.8
{y=9.2x+12.4
Use the Distributive Property to solve the equation.
- 3(x + 2) = 18
If you solve you get 50 points so pls help and no links pls
Answer:
x = -8
Step-by-step explanation:
-3x -6 = 18
-3x = 24
x = -8
Select the correct answer.
Which function is the inverse of f(x) = -x^3 - 9?
Answer:
(2)
Step-by-step explanation:
Let f(x) = y → f-¹(x) = f(y) = x, f(y) is the inverse of f(x)
Thus,
=> -x³ - 9 = y
=> - y - 9 = x³
=> (-y - 9)^(1/3) = x
=> f(y) = x
Inverse is (-y-9)^(1/3)
Replacing the variable, inverse is (-x-9)^(1/3)
Option (2)
If an object is projected upward with an initial velocity of 125 ft per sec, its height h after t seconds is h= - 16t+ 125t. Find the height of the object after 2 seconds.
Answer:
h(t) = -16t^2+125t
We need to find h(t) when t = 4 s:
h(4) = -16*4^2+125*4
h(4) = 244 ft
The height of the object after 4 seconds is 244 feet.