Studies have suggusted that twins, in their early years, tend to have lower IQs and pick up language more slowly than non-twins. The slower intellectual growth may be caused by benign parental neglect. Suppose it is desired to estimate the mean attention time given
to twins per week by their parents. A sample of 26 sets of two-year-old twin boys was taken, and after one week the attention time
received was recorded. The mean was found to be 27.4 hours with a standard deviation of 11,2 hours. Use this information to contruc
a 98% confidence interval for the mean attention time given to all twin boys by their parents, assuming that the population is
approximately normally distributed, Round the endpoints to one decimal place.
Confidence interval:( , )
Answer:
Confidence interval: (21.9, 32.9).
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used 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 = 26 - 1 = 25
98% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 25 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.98}{2} = 0.99[/tex]. So we have T = 2.485
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 2.485\frac{11.2}{\sqrt{26}} = 5.5[/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 27.4 - 5.5 = 21.9 hours
The upper end of the interval is the sample mean added to M. So it is 27.4 + 5.5 = 32.9 hours
Confidence interval: (21.9, 32.9).
Angela bought 4 bottles of soda for a party. Each bottle was 2-liters. How many gallons of soda did she buy? Use 1 gallon = 3.785 liters
Answer:
no sé amigo Thu tcug
Step-by-step explanation:
v8ftuuurk
I’ll mark ya brainless who can help?
Answer:
c
Step-by-step explanation:
Answer:
C
Step-by-step explanation:
You have 12 marbles and you have 4 of each color.
A sector has a radius of 12 centimeters and an angle of 65 degrees. Find it's arc length.
A. 18.2 cm
B. 13.6 cm
C. 12.6 cm
D. 14.6 cm
The arc length will be option B. 13.6 cm.
How to find the relation between angle subtended by the arc, the radius and the arc length?[tex]2\pi^c = 360^\circ = \text{Full circumference}[/tex]
If radius of the circle is of r units, then
[tex]1^c \: \rm covers \: \dfrac{circumference}{2\pi} = \dfrac{2\pi r}{2\pi} = r\\\\or\\\\\theta^c \: covers \:\:\: r \times \theta \: \rm \text{units of arc}[/tex]
The superscript 'c' shows the angle measured in radians.
Given; A sector has a radius of 12 centimeters and an angle of 65 degrees.
So we input our values in the formula:
2π (12) x 65/360
= 24π x 65/360
= 13.6
Hence, the arc length will be option B. 13.6 cm.
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I need some help with this,and have this done correctly for brainliest.
#5 = 1
Because you have to find x of (-3) and then you find 1.
#6 = 1
The vertical line doesn't represent a function but horizontal line if passed once represents the function.
#7 = 4
You can just plug in the x values into the equation and solve for y and math the answer to the y data.
1) Choice 1, is the correct answer because -3 on the x-axis touches the graph at 6 on the y-axis.
2) Choice 2, is the correct answer. It doesn't pass the horizontal line because it passes through more than one line on the graph. However, it does pass the vertical line test, which only passes through one line and makes this graph a function.
3) Choice 4, is the correct answer. If you use an online graphing tool, you can match up the points on one of these tables. Choice 4 only seems to fit all on these into f(x) = -2x + 6 equation.
Hope this helps :)
Ravi has ridden 44 miles of a bike course. The course is 55 miles long. What percentage of the course has Ravi ridden so far?
Answer:
80%
Step-by-step explanation:
To find the percent that he has ridden, divide the number of miles he has ridden by the total length of the course
44/55
= 0.8
So, Ravi has ridden 80% of the course
Answer:
80%
Step-by-step explanation:
There are 55 miles 1/5=11 miles so 44 miles=4/5
4/5=80%
In 2 years, Duncan wants to buy a bicycle that costs $400.00. If he opens a savings account that earns 11% interest compounded annually, how much will he have to deposit as principal to have enough money in 2 years to buy the bike?
Answer:
Current deposit amount = $324.65 (Approx.)
Step-by-step explanation:
Given:
Cost of bicycle = $400
Future amount = $400
Rate of interest = 11% = 0.11
Number of year = 2 year
Find:
Current deposit amount
Computation:
Compound interest formula
A = P[1+r]ⁿ
Future amount = Current deposit[1+Rate of interest]ⁿ
400 = Current deposit[1+0.11]²
400 = Current deposit[1.11]²
400 = Current deposit[1.2321]
Current deposit amount = 400 /1.2321
Current deposit amount = $324.65 (Approx.)
A data set has a median of 48, and six of the numbers in the data set are less than
median. The data set contains a total of n numbers.
If n is odd, and exactly one number in the data set is equal to 48, what is the value of
n?
A 13
B 16
C 15
D 17
The sum of 1/2 and 1/3 is?
Answer:
5/6
Step-by-step explanation:
Primalia knows there are 3 feet in 1 yard. She writes the equation 3= to find the number of yards, , in any number of feet, .
Use the drop-down menus to complete the statements about Primalia's equation.
The word choices for the first part is "greater than" or "less than".
The word choices for the second part is "greater than" or "less than"
The word choices for the third part is "will" or "will not"
The word choices for the fourth part is "3 x f = y", "3 + f = y", "3 x y = f", or "3 + y = f"
Answer:
Step-by-step explanation:
1. Greater than
2. Greater than
3. will
4. 3 × f = y
A research scholar wants to know how many times per hour a certain strand of virus reproduces. The mean is found to be 4 reproductions and the population standard deviation is known to be 2.3. If a sample of 1083 was used for the study, construct the 99% confidence interval for the true mean number of reproductions per hour for the virus. Round your answers to one decimal place.
Answer:
The 99% confidence interval for the true mean number of reproductions per hour for the virus is between 3.8 and 4.2.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.99}{2} = 0.005[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.005 = 0.995[/tex], so Z = 2.575.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 2.575\frac{2.3}{\sqrt{1083}} = 0.18[/tex]
Rounding to one decimal place, 0.2.
The lower end of the interval is the sample mean subtracted by M. So it is 4 - 0.2 = 3.8 reproductions
The upper end of the interval is the sample mean added to M. So it is 4 + 0.2 = 4.2 reproductions.
The 99% confidence interval for the true mean number of reproductions per hour for the virus is between 3.8 and 4.2.
Three times the sum of a number and three is equal to six times the number, minus three. Find the number
The number is ?
Answer:
n = 4
Step-by-step explanation:
3(n + 3) = 6n - 3
3n + 9 = 6n - 3
12 = 3n
n = 4
ava walks to the end of her section of trail and back in 90 minutes Luis walks his his section of the trail in 1 3/4 hours. Who walks longer?
Answer:
Luis
Step-by-step explanation:
One hour is 60 minutes total, leaving and extra 30 minutes for Ava, which is half of 60. So, in fraction form, she walked 1 1/2 OR 1 2/4 hours, which is less than Luis. He walked about an hour and 45 minutes total, or 105 minutes.
PLEASE ANSWER FAST! WILL GIVE BRAINLIEST
Answer:
B po
Step-by-step explanation:
Kase interquartile range po yan
Please help I’ll give points + brainalist
Answer:
hi sjsjsejrjhrhrjrjehhwhkekekhehe
Step-by-step explanation:
d part is the answer
it it was the same as the last time you had
A garden has a length of (x + 2) feet and a width of (2x - 1) feet. The garden’s total area is 88 square feet. Find the length.
Answer:
x= 29
Step-by-step explanation:
Which equation demonstrates the distributive property?
Answer:
B-36*8=8*36
The distributive property is just using the same numbers except it's just switched around but hte same numbers are in the problem/equation.
Hope this helps!
Have a great day!
- Hailey
Look below for an example!
Help pleaseee! Whats the answer
Answer:
The answer is 16 for the blue dot
I'm think it's 16
Step-by-step explanation:
This is because it seems that it jumps from 0 to 4. So you add four to the number 4...
Find the area of this circle. Use 3.14 for 62 in.
Kela wants to visit a friend who lives 8 kilometres away. She'll ride the Subway as she can before walking the rest of the way. first, she needs to buy an access pass that costs $5.50 there is also a fee of $1.25 first stop Kela doesn't want to spend more than $15 on the trip so she wants to know the largest number of stops she can afford write an inequality to solve this problem.
Pls answer fast I'll mark brainliest
Answer:
Kela will be able to travel for 7 stops before her money runs out.
Step-by-step explanation:
Since Kela wants to visit a friend who lives 8 kilometers away, and she'll ride the subway as she can before walking the rest of the way, and she needs to buy an access pass that costs $ 5.50 and there is also a fee of $ 1.25 for each stop, if Kela doesn't want to spend more than $ 15 on the trip, to determine the largest number of stops she can afford, the following calculation must be performed:
(15 - 5.5) / 1.25 = X
9.5 / 1.25 = X
7.6 = X
Therefore, Kela will be able to travel for 7 stops before her money runs out.
Find the area of the shaded region in the figure below, if the radius of the outer circle is 8 and the radius of the inner circle is 4. Keep your answer in terms of π.
Answer:
48 π
Step-by-step explanation:
Area of Circle =πr∧2
Big Circle Area = π(8)∧2 = 64π
Small Circle Area =π(4)∧2= 16π
Shaded Region = 64π - 16π = 48π
If Houston is six hours behind London, what time would it be in Houston if it were 9 p.m. in London?
Answer:
3:00 p.m. in Houston.
Step-by-step explanation:
need to solve
7y+32;y=9
Answer:
95
Step-by-step explanation:
Have a great day
Two hundred Dickinson parents were surveyed; 25% prefer year-round school. What fraction represents the number of parents who prefer year-round school?
315 points)
What is the slope of a line parallel to y =-1/2x+6
A) 1/2
B) 2
C) -1/2
D) -2
Answer:
The slope is -1/2
Step-by-step explanation:
The Y-intercept is (0,6)
Question 17
17. Find the scale factor that was used in the dilation shown.
Answer:
We are missing a picture, we can't see the dilation they are referring to. The photo is just showing the answer options, so without the dilation it can't be answered.
Step-by-step explanation:
I WILL MARK YOU AS BRAINLIST PLEASW HELPPP
Answer:
A = 30
Step-by-step explanation:
it's a 30,60,90 triangle by the sides but to prove it:
sohcahtoa
cos A = 3√2/2√6 = 4.24/4.899 = .865
A = 30°
Cuáles son los elementos de un polinomio
The half-life of a radioactive kind of tellurium is 2 months. If you start with 40 grams of it, how much will be left after 4 months?
Answer:
10 g
Step-by-step explanation:
40/2 = 20 g
20/2 = 10 g
If half-life of a radioactive kind of tellurium is 2 months. If you start with 40 grams of it, then 10 gm of it left after 4 months.
What is Half life?Half-life is the time required for a quantity to reduce to half of its initial value.
Given,
The half-life of a radioactive kind of tellurium is 2 months
It started with 40 grams of radioactive kind of tellurium
As given, half is for two months
In first two months it becomes 20 gm
40/2= 20gm
In second two months the 20 gm is reduced by half
20 gm/2=10gm.
Hence, 10gm of radioactive kind of tellurium is left after 4 months.
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can u help me with this
Answer:
1/500 = 0.002, 2 and 6/10 = 2.6, 3 and 2/25 = 308%, 0.0025 = 25%
Step-by-step explanation: