Answer:
12950
Step-by-step explanation:
A pharmacologist measured the concentration of dopamine in the brains of several rats. The mean concentration was 1,269 ng/gm and the standard deviation was 145 ng/gm.4 What was the standard error of the mean if:_______.(a) 8 rats were measured?
(b) 30 rats were measured?
Answer:
51.265242 ng/gm ; 26.473257 ng/gm
Step-by-step explanation:
The standard error of the mean = standard deviation / √sample size
Given that:
mean concentration = 1,269 ng/gm
Standard deviation (s) = 145 ng/gm
Standard Error if 8 rats were measured :
Sample size (n) = 8
Standard Error = s / √n
Standard Error = 145 / √8
Standard Error = 145 / 2.8284271
Standard Error = 51.265242 ng/gm
If 30 rats were measured :
Standard Error = 145 / √30
Standard Error = 145 / 5.4772255
Standard Error = 26.473257 ng/gm
Jack has a saving account of value $65,550 at the start. The saving account has an interest rate of 3% that is compounded every six months. How long will it take Jack to have $100,000 in his account?
Given:
Principal value = $65,550
Rate of interest = 3% compounded every six month
To find:
The taken to have $100,000 in Jack's account.
Solution:
The formula for amount is
[tex]A=P(1+\dfrac{r}{n})^{nt}[/tex]
where, P is principal, r is rate of interest, n is number of times interest compounded in an year, t is time in number of years.
Interest compounded every six month. It means, interest compounded 2 times in an year.
Substitute A=100000, r=0.03 and n=2 in the above formula.
[tex]100000=65550(1+\dfrac{0.03}{2})^{2t}[/tex]
[tex]\dfrac{100000}{65550}=(1+0.015)^{2t}[/tex]
[tex]1.525553=(1.015)^{2t}[/tex]
Taking log on both sides.
[tex]\log (1.525553)=\log (1.015)^{2t}[/tex]
[tex]\log (1.525553)=2t\log (1.015)[/tex]
[tex]\dfrac{\log (1.525553)}{2\log (1.015)}=t[/tex]
[tex]t=14.1838928[/tex]
[tex]t\approx 14.18[/tex]
Therefore, after 14.18 year the amount will reach at $100,000 or we can say that in 15th year the amount will reach at $100,000.
I need help answering. Thanks.
Answer:
28
Step-by-step explanation:
C or B's so 30% + 40% = 70% so:
70/100 multiplied by 40 because 40 students
7/10 times 40 = 28
A.4
B.3
C.6
D.5........ please help
Answer:
The answer is
A. 4
Step-by-step explanation:
Given: BD is perpendicular to AC, measure DBA = 7x+6. Find x
Answer:
x = 12
Step-by-step explanation:
[tex] \because BD \perp AC... (given) \\\\
\therefore m\angle DBA =90\degree... (1)\\\\
\because m\angle DBA=(7x + 6)\degree... (2)\\[/tex]
From equations (1) & (2)
[tex](7x + 6)\degree= 90\degree \\\\
7x + 6 =90\\\\
7x = 90 - 6\\\\
7x = 84\\\\
x = \frac{84}{7}\\\\
\huge \orange {\boxed {x = 12}} [/tex]
Write an equation and solve. Round to the nearest hundredth where necessary. What is 35% of 63?
is -3/4 rational or irrational?
is the square root of 2 rational or irrational?
is 2π rational or irrational?
is 3.75 rational or irrational?
is 2 1/8 rational or irrational?
need help please full question in image
PLEASE HELP ME BRAINLIEST AND 20 POINTS
What is the domain of f(x) = 35x?
O all real numbers
O positive numbers and zero
O all integers
O whole numbers
Do not guess please this is important and, please explain your answer. Thank you
Ratios
Express each ratio as a fraction in the simplest for
MI
1) 18 pounds to 22 pounds
Answer:
h
Step-by-step explanation:
eteujj
Someone please help answer completely !
Answer:
the answer is [tex]T=\frac{VP}{8}[/tex]
Step-by-step explanation:
V=[tex]\frac{8T}{P}[/tex]
you need to make T the subject of the formula:
step1: multiply P for both sides.
V=[tex]\frac{8T}{P}[/tex]
VP=8T
step2: divide by 8 for both sides.
T=[tex]\frac{VP}{8}[/tex]
the answer is [tex]T=\frac{VP}{8}[/tex]
⚠️⚠️⚠️⚠️NEED HELP MARKING PEOPLE AS BRAINLIST!
I believe its a reflection
Sorry if im wrong
The distance an object falls is directly proportional to the square of the time it falls. A ball falls 144 feet in 3 seconds. How far will an object fall in 4 seconds?
Answer:
d = 256 ft.
Step-by-step explanation:
The distance an object falls is directly proportional to the square of the time it falls.
First, we name the variables.
Let d= the distance.
t= time
Write the formula for direct variation, where y varies directly with the square of x.
y=kx2
We will use d in place of y and t in place of x.
d=kt2
Substitute the given values for the variables.
d=144whent=3144=k⋅32
Solve for the constant of variation.
144916=k⋅99=k
Write the equation that relates d and t.
d=kt2
Substitute in the constant of variation.
d=16t2
Find d when t=4.
Write the equation that relates d and t.
d=16t2
Substitute the given value for t.
d=16⋅42
Simplify.
d=256
An object will fall 256 feet in 4 seconds.
The required distance fall by fall in 4 seconds is 192 feet.
Given that,
The distance an object falls is directly proportional to the square of the time it falls. A ball falls 144 feet in 3 seconds, how far will an object fall in 4 seconds is to be determined.
In mathematics, it deals with numbers of operations according to the statements. There are four major arithmetic operators, addition, subtraction, multiplication, and division.
here,
The rate of fall of the ball = 144 / 3
= 48 feet second
Now distance fall by the ball in 4 seconds = 48 * 4 = 192 feets.
Thus, the required distance fall by fall in 4 seconds is 192 feet.
Learn more about arithmetic here:
brainly.com/question/14753192
#SPJ2
In how many ways can you arrange the books A, B, C, and D on a bookshelf if books A and C must remain neighboring?
Homer is 30 feet below sea level and Marge is 45 feet above sea level. Bart’s elevation is at the exact midpoint of those two values. What is the expression that model this problem, and which is Bart’s elevation?
Answer:
14.5 feet
Step-by-step explanation:
the midpoint is halfway from 30 to 45 so be(bart elevation) b.e = 45 - 30 / 2
7.5 m above sea level
__________________________________________________________
Step-by-step explanation:We are given:
The elevation of Homer = -30 feet [30 feet below sea level]
The elevation of Marge = +45 feet [45 feet above sea level]
The elevation of Bart is at the exact mid-point of the elevations of Homer and Marge
The elevation of Bart:
We are given that the elevation of Bart is at the exact mid-point of the elevations of Homer and Marge
So, Half the distance between the elevation of Homer and Marge is the elevation of Bart
Elevation of Bart (with respect to the elevation of Homer) =
(elevation of Marge - Elevation of Homer) / 2
replacing the variables with the suitable values:
(+45 - (-30))/2
(45 + 30) / 2
75 / 2
Elevation of Bart (w.r.t. Homer) = 37.5 feet
Since this is the elevation of Bart with respect to Homer, we can say that Bart is 37.5 m above Homer
So, we can say that:
Elevation of Bart (w.r.t Homer) = Elevation of Bart - Elevation of Homer
replacing the values
37.5 = Elevation of Bart -(-30)
37.5 = Elevation of Bart + 30
Elevation of Bart = 7.5 m above sea level [subtracting 30 from both sides]
Please help with my homework
It's 65. Because you add the other angles and get 90+25 and get 115. 180 -115 = 65.
Answer:
c=65°
Step-by-step explanation:
180-90=90
90-25=65
hopefully this helps :)
how many terms are there in the expression 2x - 3y + 8?
Answer:
Three. 2x, -3y, and 8.
Step-by-step explanation:
For every constant or variable, there is a term.
In this expression, there are two variables (x and y) and there is a constant (8).
Hence, there are three terms.
Hope this helped!
convert the common fraction into decimal fraction
[tex] \frac{3}{4} [/tex]
Answer:
We know that 3/4=0.75.When expressed as decimal fraction it is 75/100
Which equation represents a linear function?
Group of answer choices
y – 5 = x(–x + 2)
y – 5 = x – 20
y(x – 1) = 9
y(y – 1) = x + 25
Find the value of K. The diagram is not to scale. Explain your answer.
Answer:
639 lo hago para conseguir puntos ;V
Step-by-step explanation:
help pls
What is the solution to this system of equations?
x = 12 − y
2x + 3y = 29
Answer:
Step-by-step explanation:
If f(x)= -4x + 3 and g(x) = 3x² + 2x - 4 find (f+g)(x)
Answer:
A
Step-by-step explanation:
We have the two functions:
[tex]f(x)=-4x+3\text{ and } g(x)=3x^2+2x-4[/tex]
And we want to find (f+g)(x).
Note that this is the same thing to f(x)+g(x). Therefore:
[tex]\begin{aligned} (f+g)(x)&=f(x)+g(x) \\ &=(-4x+3)+(3x^2+2x-4) \end{aligned}[/tex]
We simply substituted them for their equations.
Simplify. Combine like terms:
[tex]=(3x^2)+(-4x+2x)+(3-4)[/tex]
Add:
[tex]=3x^2-2x-1[/tex]
Hence, our answer is A.
Sarah has saved 254 pound coins. She puts the pound coins into bags.
There are 20 pound coins in each full bag of coins. Sarah is going to take all her full bags of coins to the bank.
She can only take up to 5 full bags of coins to the bank each day.
Sarah wants to go to the bank on as few days as possible.
On how many days will Sarah need to go to the bank?
Answer:
Step-by-step explanation:
So for the fewest days it would be 3 days. The reason for that is because she has 254 pound coins. And she can inly take 5 bags to the bank a day, all of those 5 bags have 100 pound coins in them. If she take 2 days and get 200 pound coins to the bank. Then on the third day she would only have to bring three bags. So your answer for the fewest days possible is three days!
Hope it helps
Write a like term to: -5y
Answer:
-7y
Step-by-step explanation:
As long as the variable and exponent is the same, they are like terms
Answer: 68y
There are infinitely many ways to answer this. All you need to do is pick your favorite number and then stick y at the end of it. The terms -5y and 68y are like terms because they have the same variable attached.
You can think of 68y-5y as having 68 yoyos and then subtracting off 5 yoyos to get 63 yoyos when all is said and done. In terms of algebra, we would write 68y-5y = 63y.
Find the distance of a line given the following points. R(3, 1), W(-1, -2)
Answer:
[tex]\sqrt{13}[/tex]
Step-by-step explanation:
we can solve this using the distance formula: [tex]\sqrt{(x_{2}-x_1)^{2} + (y_{2}-y_1)^{2}}[/tex]
[tex]x_1, y_1[/tex] is (3, 1)
[tex]x_2, y_2[/tex] is (-1, -2)
[tex]\sqrt{(1-3)^2 + (-2-1)^2}[/tex]
which simplifies to: [tex]\sqrt{(-2)^2 + (-3)^2}[/tex]
then: [tex]\sqrt{2^2 + 3^2}[/tex] or: [tex]\sqrt{4+9}[/tex]
your final answer is: [tex]\sqrt{13}[/tex] or about 3.61
I have $100 and I want to buy tshirt that cost $10 and sweatshirts that cost $20 how many tshirts and sweatshirts can I buy
Answer:
10 tshirts or 5 sweatshirts
Step-by-step explanation:
One t-shirt + one sweatshirt = $30.
We know that $100 ÷ $30 = 3 times with $10 left over.
This leads to the conclusion that you can buy 4 t-shirts and 3 sweatshirts.
Paul opened a bakery. The net value of the bakery
(in thousands of dollars) t months after its creation is
modeled by
v(t) = 24
12t - 14
Paul wants to know what his bakery's lowest net
value will be
Rewrite the function in a different form
(factored or vertex) where the answer appears
as a number in the equation.
Answer: v(t)= 2(t-3)^2-32
-32 thousand dollars
Step-by-step explanation:
Did the quiz
Answer:
the first one is correct
Step-by-step explanation:
the ratio 60 miles per hour is an example of a because it has two measurements having different units of measure
Answer:
180
Step-by-step explanation:
Answer: ejejejwjfmfmdnc
Step-by-step explanation:
solve for x, and explain how u did it :)
Answer:
71 I THINK
Step-by-step explanation:
since the angles on the base of an isosceles triangle equal each other you would wright 71=x as your equation. there is nothing else to solve so 71 is your answer
I need help Nkaocjsjbsiss
Answer:
46
Step-by-step explanation:
it wouldn't change if it was to be rotated