Answer:
The 99% confidence interval for this sample mean is between 2.895 ppb and 2.903 ppb.
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 = 7 - 1 = 6
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 6 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.99}{2} = 0.995[/tex]. So we have T = 3.7074
The margin of error is:
M = T*s = 3.7074*0.001 = 0.004
In which s is the standard deviation of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 2.899 - 0.004 = 2.895 ppb.
The upper end of the interval is the sample mean added to M. So it is 2.899 + 0.004 = 2.903 ppb.
The 99% confidence interval for this sample mean is between 2.895 ppb and 2.903 ppb.
Find the unit rate.
Kenny reads
3/8 page in 2/3 minutes.
Answer:
15/ 16
Step-by-step explanation: 3/2 x 5/8= 15/16
you flip 2/3 to 3/2 and multiply it
Find the number of unique permutations of the letters in the word: EXTENT
720
180
900
36
Answer:
180
Step-by-step explanation:
A word has n letters.
There are m repeating letters, each of them repeating [tex]r_{0}, r_{1}, ..., r_{m}[/tex] times
So the number of distincts ways the letters can be permutated is:
[tex]N_{A} = \frac{n!}{r_{1}! \times r_{2}! \times ... \times r_{m}}[/tex]
In this question:
Extent has 6 letters.
E and r repeat 2 times. So
[tex]N = \frac{6!}{2!*2!} = 180[/tex]
So the answer is 180.
Sa piajes egne baseball games this season. Her point totais for each game were 8. 14.4 7.6.14, 4 and 7. What was
the mean number of points she scoret per game?
Answer:
The mean number of scores per game is 8
Step-by-step explanation:
Since we know we can find the mean by adding all the numbers and dividing them by many numbers there were. Once you add 8, 14, 4, 7, 6, 4, and 7, you will get 64. Since there were 8 numbers, you divide 64 by 8 to get 8.
What is the end behavior of the graph of the polynomial function f(x)=3x^6+30x^5+75x^4
Answer:
Step-by-step explanation:
Help me please and thank you
Answer:
increasing
Step-by-step explanation:
y = 1/2x +2
This function is increasing because the slope is positive.
If the first three Fibonacci nos. are x1=1, x2=1 and x3=2, what is the value of n for which xn + xn+1 = 89 ?
Answer:
11
Step-by-step explanation:
Looking at Fibonacci numbers ;
We have:
Than X1 =1 ; X2 = 1; X3 = 2
Xn+1 = Xn + Xn-1
X3 = X2 + X1 = 1+1 =2; X4 = X3 + X2 = 2 +1 = 3; X5= X4+X3 = 3+2 = 5; X6 = X5 + X4 = 5 + 3 = 8; X7 = X6 +X5 = 8 +5 = 13; X8 = X7 + X6 = 13 + 8 = 21; X9 = X8 + X7 = 21+ 13 = 34 ; X10 = X9 + X8 = 34 +21 = 55 ; X11 = X10 + X9 = 55 +34 = 89
We see that ; X11 gives 89 so the value of n = 11
To the nearest tenth, find the area of a circle with d = 15km. Use 3.14 for . Remember: you must find the radius before you use the formula
Answer:
radius r = 7.5 km
diameter d = 15 km
circumference C = 47.1238898 km
area A = 176.714587 km2
Step-by-step explanation:
math
A builder buys a piece of property with 16.1 acres of land to develop a new set of walking trails and baseball fields. The builder plans to use 0.33 of the property for baseball fields. How many acres will the builder use for the baseball fields?
Answer:
The builder will use 5.28 acres of land for baseball fields.
Step-by-step explanation:
This question can be solved using a rule of three.
The property has 16.1 acres of land. This is 100% = 1. 33% will be used for baseball fields. How much is 0.33?
16.1 - 1
x - 0.33
[tex]x = 16*0.33 = 5.28[/tex]
The builder will use 5.28 acres of land for baseball fields.
A polar bear migrate north during winter to hunt for its food on sea ice. The daily average temperature decreases 3°C for every 100 km traveled. At the start of the bear's journey, the temperature is 2"C. What is the temperature after 200 km of its journey ?
Answer:
The average temperature after 200 kilometers of journey is -4 °C.
Step-by-step explanation:
The situation shows that change in average temperature is directly proportional to travelled distance:
[tex]T = 2^{\circ}C - \frac{3^{\circ}C}{100\,km} \cdot (200\,km)[/tex]
[tex]T = -4^{\circ}C[/tex]
The average temperature after 200 kilometers of journey is -4 °C.
Answer:
The temperature after 200 km of its journey is -4°C
Step-by-step explanation:
To find the new temperature, first, you need to find how much the temperature decreases, and then subtract this temperature decrease to the initial temperature.
The temperature decreases 3°C for every 100 km travelled, then, after 200 km the temperature decreases 2*3 = 6 °C.
At the start of the bear's journey, the temperature was 2 °C, after 200 km the temperature is 2 - 6 = -4°C
write 820.341 in scientific notation
solve 5tanx= 5sqrt3 for 0
Answer:
60 degrees
Step-by-step explanation:
5 tan x = 5 root 3
tan x = root 3
sin x / cos x = root 3
(root(3) / 2) / (1/2) = root 3
sin x = root(3)/2
cos x = 1/2
x = 60 degrees
Gavin, Colin and Dan share some sweets in the ratio 7:3:2. Gavin gets 75 more sweets than Dan. How many sweets does Colin get?
Answer:
45 sweets.
Step-by-step explanation:
Gavin gets 7(7+3+2) = 7/12 of the sweets.
Dan gets 2 /12 so Gavin gets 7/2 times as much as Dan
Let Dan get x sweets then
x + 75 = 7x /2
7x/2 - x = 75
5x/2 = 75
x = 75 * 2/5 = 30 sweets.
So Dan gets 30 sweets , Gavin gets 105 sweets and Colin gets 3/2 * 30
= 45 sweets.
Factor 4x^3 + 40x^2 + 100x
Answer:
4 x (x + 5)^2
Step-by-step explanation:
Factor the following:
4 x^3 + 40 x^2 + 100 x
Factor 4 x out of 4 x^3 + 40 x^2 + 100 x:
4 x (x^2 + 10 x + 25)
The factors of 25 that sum to 10 are 5 and 5. So, x^2 + 10 x + 25 = (x + 5) (x + 5):
4 x (x + 5) (x + 5)
(x + 5) (x + 5) = (x + 5)^2:
Answer: 4 x (x + 5)^2
According to the most recent census, the average total yearly expenses of households in Wake County is $45,900. It is also known that the distribution of household expense in Wake County is strongly skewed to the right with a standard deviation of $8,370. A researcher is going to randomly select a sample of 7 households from Wake County.
1. Which of the following is true?
Select all that apply:
a. The sampling distribution of the sample mean will have a smaller standard deviation than the population.
b. The sampling distribution of the sample mean will have a different standard deviation than the population.
c. The shape of the sampling distribution of the sample mean will be skewed right.
d. The sampling distribution of the sample mean will have a larger standard deviation than the population.
e. We cannot tell what the shape of the sampling distribution of the sample mean will look like.
f. The shape of the sampling distribution of the sample mean will be approximately symmetric.
Answer:
a. The sampling distribution of the sample mean will have a smaller standard deviation than the population.
b. The sampling distribution of the sample mean will have a different standard deviation than the population.
c. The shape of the sampling distribution of the sample mean will be skewed right.
Step-by-step explanation:
Whats happens when the value of the expression c + 2 as c increase
Answer:
c+2 increases linearly with c. That means that if c increases by 1, c+2 will increase by 1; if by 2, c+2 will increase by 2.
Step-by-step explanation:
Which situation can be represented by the equation Y equals 74X
Answer:
X: amount of a spare part of price $74 per unit.
Y: cost of purchasing X spare parts.
Step-by-step explanation:
We can imagine that X represents the amount of an object, for example a car spare part, which price is $74 per unit.
Then, Y would represent the cost of purchasing X units of that spare part.
What’s the correct answer for this? Select the ones that apply
Answer:
B, C and E
Step-by-step explanation:
1) Proving that opposite sides have equal slopes as they are parallel also
2) Proving that opposite sides are parallel and equal
Write using only positive exponents. 16x^4z^4/36x-2yz^0
Answer:
Step-by-step explanation:
16x^4y^-3z^4 / 36x^-2yz^0
16x^4y^-3z^4 = 16x^4z^4/y^3
36x^-2yz^0 = 36x^-2y(1) =36x^-2y = 36y/x^2
16x^4y^-3z^4 / 36x^-2yz^0
= (16x^4z^4/y^3) / (36y/x^2)
= 16x^4z^4/y^3 * x^2/36y
= (4/9)x^6z^4/y^4
or another way
fist multiply it out
f(x) = 4x^(3/5) - x^(8/5)
now differentiate knowing d/dx(x^n) = n x^(n-1)
to get
4*(3/5) x^(-2/5) - 8/5 x^(3/5)
simplify to get
12/5/x^(2/5) - 8/5 x^(3/5)
If this is what your looking for please give me brainiest, i have done this problem in the past so i know how to solve it :)
4(1 - x) + 2 x= -3( x + 1)
Answer:
x = -7
Step-by-step explanation:
Solve for x:
4 (1 - x) + 2 x = -3 (x + 1)
4 (1 - x) = 4 - 4 x:
2 x + 4 - 4 x = -3 (x + 1)
2 x - 4 x = -2 x:
-2 x + 4 = -3 (x + 1)
Expand out terms of the right hand side:
4 - 2 x = -3 x - 3
Add 3 x to both sides:
3 x - 2 x + 4 = (3 x - 3 x) - 3
3 x - 3 x = 0:
3 x - 2 x + 4 = -3
3 x - 2 x = x:
x + 4 = -3
Subtract 4 from both sides:
x + (4 - 4) = -4 - 3
4 - 4 = 0:
x = -4 - 3
-4 - 3 = -7:
Answer: x = -7
Answer:
X=-7
Step-by-step explanation:
Solve: x=4+(4x-4)1/2 x = 2
x = 10
x = 2 or x = 10
no real solution
Answer:
No real solution- Not any of the options anyway
Step-by-step explanation:
So I replaced the x's with the two possible equations and then tried to solve...
2=4+(4x2-4)1/2
2=4+(8-4)1/2
2=4+(4)1/2
2=8(1/2)
2=4 Which is not true
10=4+(4x10-4)1/2
10=4+(40-4)1/2
10=4+36(1/2)
10=40(1/2)
10=20 Which is also not true
Therefore, there is no real solution
Answer:
B: x = 10 on Edge 2020
Step-by-step explanation:
Students at a certain school were surveyed, and it was estimated that 20% of college students abstain from drinking alcohol. To estimate this proportion in your school, how large a random sample would you need to estimate it to within 0.08 with probability 0.95, if before conducting the study (a) you are unwilling to predict the proportion value at your school and (b) you use the results from the surveyed school as a guideline.
Answer:
a) A sample size of at least 251 students is needed.
b) A sample of at least 97 students is needed.
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].
(a) you are unwilling to predict the proportion value at your school
We need a sample size of at least n.
n is found when M = 0.08.
We wont predict a proportion value for the school, so we use [tex]\pi = 0.5[/tex]
So
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.08 = 1.96\sqrt{\frac{0.5*0.5}{n}}[/tex]
[tex]0.08\sqrt{n} = 1.96\sqrt{0.5*0.5}[/tex]
[tex]\sqrt{n} = \frac{1.96\sqrt{0.5*0.5}}{0.08}[/tex]
[tex](\sqrt{n})^{2} = (\frac{1.96\sqrt{0.5*0.5}}{0.08})^{2}[/tex]
[tex]n = 150.1[/tex]
Rounding up
A sample size of at least 251 is needed.
(b) you use the results from the surveyed school as a guideline.
Now we have that [tex]\pi = 0.2[/tex]
So
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.08 = 1.96\sqrt{\frac{0.2*0.8}{n}}[/tex]
[tex]0.08\sqrt{n} = 1.96\sqrt{0.2*0.8}[/tex]
[tex]\sqrt{n} = \frac{1.96\sqrt{0.2*0.8}}{0.08}[/tex]
[tex](\sqrt{n})^{2} = (\frac{1.96\sqrt{0.2*0.8}}{0.08})^{2}[/tex]
[tex]n = 96.04[/tex]
Rounding up
A sample of at least 97 students is needed.
Which graph shows the solution set for 2 x + 3 greater-than negative 9? A number line going from negative 8 to positive 2. An open circle is at negative 3. Everything to the left of the circle is shaded. A number line going from negative 8 to positive 2. An open circle is at negative 3. Everything to the right of the circle is shaded. A number line going from negative 8 to positive 2. An open circle is at negative 6. Everything to the left of the circle is shaded. A number line going from negative 8 to positive 2. An open circle is at negative 6. Everything to the right of the circle is shaded.
Answer:
3
Step-by-step explanation:
because is a hcsbjmcscin C d
Answer:
the right answer is x = 3 and x= -1/2
Step-by-step explanation:
I took the test.
Triangle RST is drawn inside rectangle RSNM. Point T is halfway between points M and N on the rectangle. The length of side RS is 9 in. and the length of side RM is 8 in. Show your work
The question is not complete. The complete question is;
Triangle RST is drawn inside rectangle RSNM. Point T is halfway between points M and N on the rectangle. The length of side RS is 9 in. and the length of side RM is 8 in.
1) What is the area of triangle RST?
2)What is the ratio of area of triangle RST to area of triangle RMT?
3) What is the area of rectangle RSMN to area of triangle TSN?
Diagram is attached.
Answer:
1) 36 sq.in
2) 2:1
3) 4:1
Step-by-step explanation:
1) Area of triangle is; ½ × base × height.
For triangle RST, base = 9 in and height = 8 in
Thus, area of triangle RST = ½ × 9 × 8
= 36 sq.in
2)Area of triangle RMT = ½ × 8 × 9/2
= 18 sq.in
Ratio of area of RST to area of RMT = 36/18 = 2:1
3)Area of triangle TSN = ½ × 8 × 9/2 = 18 sq.in
Area of Rectangle RSNM = Length x width = 9 × 8 = 72 sq.in
Ratio of Area of Rectangle RSNM to Area of triangle TSN = 72/18 = 4:1
How many points appears in this figure ?
Answer:
5?
Step-by-step explanation:
I think you would count the middle point. But i don't completely know...
What is the answer for numbers 9 and 10
Answer:
I think they're both trick questions because there are no like terms
Step-by-step explanation:
Determine if the set is a Pythagorean triple
Answer:
Pythagorean Triples are sets of whole numbers for which the Pythagorean Theorem holds true. The most well-known triple is 3, 4, 5. This means that 3 and 4 are the lengths of the legs and 5 is the hypotenuse.
When the volume of a gas is
changed from mL to 852 mL,
the temperature will change from
315°C to 452°C.
Answer: The initial volume is 593.76mL
Step-by-step explanation:
As you do not say anithing about the pressure, i guess that the pressure remains constant.
If the gas is an ideal gas, we have:
P*V = n*R*T
where P is pressure, n is number of moles and R is a constant.
Now, initially we have:
P*Vi = n*R*315°C
finally we have:
P*825mL = n*R*452°C
Now we can take the quiotient of those two equations and get:
(P*Vi)/(P*852mL) = (n*R*315°C)/( n*R*452°C)
Now we have:
Vi/852mL = 315/452
Vi = (315/452)*852mL = 593.76mL
So when we expand the gas at constant pressure, we increase the temperature.
Answer:
691 mL
Step-by-step explanation:
Drag each tile to the correct location. Not all tiles will be used.
The ratio of the lengths of the radii of two spheres is 5 : 8. What is the ratio of the surface area of the smaller sphere to the surface area of the larger sphere?
1
5
8
25
40
64
125
512
Answer:
25:64
Step-by-step explanation:
surface : 4×pi×R^2
R1 = 5x
R2 =8x
4piR1^2 / 4piR2^2 = R1^2/R2^2 = 5x^2/8x^2 = 25x^2/64x^2 = 25/64
100 POINTS PLEASE ANSWER IM BEGGING YOU!!!!!!
Answer:
[tex]4 \sqrt{5}[/tex]
Step-by-step explanation:
[tex]\sqrt{80}[/tex]
80 can be written as a product of 16 and 5.
[tex]\sqrt{16 \times 5}[/tex]
Distribute the square root to both terms.
[tex]\sqrt{16} \times \sqrt{5}[/tex]
16 is a perfect square 4×4.
[tex]4 \times \sqrt{5}[/tex]
Answer:
4 * sqrt(5)
Step-by-step explanation:
sqrt(80)
sqrt(16*5)
We know that sqrt (ab) = sqrt(a) sqrt(b)
sqrt(16) sqrt(5)
4 * sqrt(5)
plz help me this is hard for me
Answer:
it is so simple lol
Step-by-step explanation:
just know that that angle is 90 degrees which means that you should do 90-41
Answer:
49
Step-by-step explanation:
90*-41*=49