9514 1404 393
Answer:
$500
Step-by-step explanation:
Bruno's fraction of the total contribution was ...
Bruno / Total = $20/($25 +20 +35) = 20/80 = 1/4
Then Bruno's share of the earnings is this same fraction, so is ...
(1/4) × ($2000) = $500
A statistics professor plans classes so carefully that the lengths of her classes are uniformly distributed between 47.0 and 57.0 minutes. Find the probability that a given class period runs between 51.25 and 51.5 minutes.
Answer:
0.025 = 2.5% probability that a given class period runs between 51.25 and 51.5 minutes.
Step-by-step explanation:
Uniform probability distribution:
An uniform distribution has two bounds, a and b.
The probability of finding a value between c and d is:
[tex]P(c \leq X \leq d) = \frac{d - c}{b - a}[/tex]
Uniformly distributed between 47.0 and 57.0 minutes.
This means that [tex]a = 47, b = 57[/tex]
Find the probability that a given class period runs between 51.25 and 51.5 minutes.
[tex]P(c \leq X \leq d) = \frac{51.5 - 51.25}{57 - 47} = 0.025[/tex]
0.025 = 2.5% probability that a given class period runs between 51.25 and 51.5 minutes.
If 19,200 cm2 of material is available to make a box with a square base and an open top, find the largest possible volume of the box.
Step-by-step explanation:
√19200cm²
=138.56cm
then the highest possible volume
=(138.56)³
=2660195.926cm³
The largest possible volume of the box is; V = 25600 cm³
Let us denote the following of the square box;
Length = x
Width = y
height = h
Formula for volume of a box is;
V = length * width * height
Thus; V = xyh
but we are dealing with a square box and as such, the base sides are all equal and so; x = y. Thus;
V = x²h
The box has an open top and as such, the surface are of the box is;
S = x² + 4xh
We are given S = 19200 cm². Thus;
19200 = x² + 4xh
h = (19200 - x²)/4x
Put (19200 - x²)/4x for h in volume equation to get;
V = x²(19200 - x²)/4x
V = 4800x - 0.25x³
To get largest possible volume, it will be dimensions when dV/dx = 0. Thus;
dV/dx = 4800 - 0.75x²
At dV/dx = 0, we have;
4800 - 0.75x² = 0
0.75x² = 4800
x² = 4800/0.75
x² = 6400
x = √6400
x = 80 cm
From h = (19200 - x²)/4x;
h = (19200 - 80²)/(4 × 80)
h = (19200 - 6400)/3200
h = 4 cm
Largest possible volume = 80² × 4
Largest possible volume = 25600 cm³
Read more at; https://brainly.com/question/19053087
The product of -3x and (2x+5) is …
[tex]\huge{\boxed{\boxed{ Solution ⎇}}} \ [/tex]
[tex] - 3x \times (2x + 5) \\ = - 3x \times 2x + - 3x \times 5 \\ = - 6x ^{2} - 15x[/tex]
ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ ツ
꧁❣ ʀᴀɪɴʙᴏᴡˢᵃˡᵗ2²2² ࿐
[tex] \huge\boxed{\mathfrak{Answer}}[/tex]
[tex] - 3x \times (2x + 5) \\ = - 3x \times 2x + - 3x \times 5 \\ = - 6x ^{2} - 15x [/tex]
Answer ⟶ - 6x² - 15x
Solve for X.
-6x + 14 < -28
AND 3x + 28 < 25
Answer:
1. -6x + 14 < -28
6x<42
x<7
2. 3x + 28 < 25
3x < -3
x<-1
Hope This Helps!!!
Calculate the pH of a buffer solution made by mixing 300 mL of 0.2 M acetic acid, CH3COOH, and 200 mL of 0.3 M of its salt sodium acetate, CH3COONa, to make 500 mL of solution. Ka for CH3COOH = 1.76×10–5
Answer:
Approximately [tex]4.75[/tex].
Step-by-step explanation:
Remark: this approach make use of the fact that in the original solution, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] are equal.
[tex]{\rm CH_3COOH} \rightleftharpoons {\rm CH_3COO^{-}} + {\rm H^{+}}[/tex]
Since [tex]\rm CH_3COONa[/tex] is a salt soluble in water. Once in water, it would readily ionize to give [tex]\rm CH_3COO^{-}[/tex] and [tex]\rm Na^{+}[/tex] ions.
Assume that the [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] ions in this solution did not disintegrate at all. The solution would contain:
[tex]0.3\; \rm L \times 0.2\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COOH[/tex], and
[tex]0.06\; \rm mol[/tex] of [tex]\rm CH_3COO^{-}[/tex] from [tex]0.2\; \rm L \times 0.3\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COONa[/tex].
Accordingly, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] would be:
[tex]\begin{aligned} & c({\rm CH_3COOH}) \\ &= \frac{n({\rm CH_3COOH})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].
[tex]\begin{aligned} & c({\rm CH_3COO^{-}}) \\ &= \frac{n({\rm CH_3COO^{-}})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].
In other words, in this buffer solution, the initial concentration of the weak acid [tex]\rm CH_3COOH[/tex] is the same as that of its conjugate base, [tex]\rm CH_3COO^{-}[/tex].
Hence, once in equilibrium, the [tex]\rm pH[/tex] of this buffer solution would be the same as the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex].
Calculate the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex] from its [tex]{\rm K}_{a}[/tex]:
[tex]\begin{aligned} & {\rm pH}(\text{solution}) \\ &= {\rm pK}_{a} \\ &= -\log_{10}({\rm K}_{a}) \\ &= -\log_{10} (1.76 \times 10^{-5}) \\ &\approx 4.75\end{aligned}[/tex].
PLS HELP please give an explanation if you don’t have one pls still give answer
(a) The heights of male students in a college are thought to be normally distributed with mean 170 cm and standard deviation 7.
The heights of 5 male students from this college are measured and the sample mean was 174 cm.
Determine, at 5% level of significance, whether there is evidence that the mean height of the male students of this college is higher than 170 cm.
[6]
(b) (i) The result of a fitness trial is a random variable X which is normally distributed with mean μ and standard deviation 2.4 . A researcher uses the results from a random sample of 90 trials to calculate a
98% confidence interval for μ . What is the width of this interval?
[4]
(ii) Packets of fish food have weights that are distributed with standard deviation 2.3 g. A random sample of 200 packets is taken. The mean weight of this sample is found to be 99.2 g. Calculate a 99% confidence interval for the population mean weight.
[4]
(c) (i) Explain the difference between a point estimate and an interval
Estimate. [2]
(ii) The daily takings, $ x, for a shop were noted on 30 randomly chosen days. The takings are summarized by Σ x=31 500 and
Σ x2=33 141 816 .
Calculate unbiased estimates of the population mean and variance of the shop’s daily taking. [4
Answer:
the answer is 50 but I don't know if
help? haha
solve the equation below:)
3x - 5 = 10 + 2x
Step-by-step explanation:
3x-2x=5+10 [taking variables on one side and constant on other]
x=15
soln:
3x-5= 2x+10
3x -5+5=2x+10+5 [ adding 5 on both side]
3x=2x+15
3x-2x=2x+15-2x [subtracting 2x on both side]
x=15
Ans=15
Answer:
[tex]x = 15[/tex]
Step-by-step explanation:
[tex]3x - 5 = 10 + 2x[/tex]
[tex]3x - 2x = 10 + 5[/tex]
[tex]1x = 15[/tex]
[tex]x = 15[/tex]
Hope it is helpful.....The sum of 5 consecutive integers is 505. What is the second number in this sequence?
Answer:
The second number is 100.
Step-by-step explanation:
Let the first integer be x.
Then since the five integers are consecutive, the second integer will be (x + 1), the third (x + 2), fourth (x + 3), and the fifth (x + 4).
They total 505. Hence:
[tex]\displaystyle x+(x+1)+(x+2)+(x+3)+(x+4)=505[/tex]
Solve for x. Combine like terms:
[tex]5x+10=505[/tex]
Subtract 10 from both sides:
[tex]5x=495[/tex]
And divide both sides by five. Hence:
[tex]x=99[/tex]
Thus, our sequence is 99, 100, 101, 102, and 103.
The second number is 100.
Pls help this is rlly important!! You’ll get branliest bc this is hard and I’m stuck.
the median of restaurant b's cleanliness ratings is 2.
the median of restaurant b's food quality ratings is 4.
the median of restaurant b's service ratings is 3.
:))
In a given region, the number of tornadoes in a one-week period is modeled by a Poisson distribution with mean 2. The numbers of tornadoes in different weeks are mutually independent. Calculate the probability that fewer than four tornadoes occur in a three-week period.
Answer:
0.1512 = 15.12% probability that fewer than four tornadoes occur in a three-week period.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
In which
x is the number of sucesses
e = 2.71828 is the Euler number
[tex]\mu[/tex] is the mean in the given interval.
In a given region, the number of tornadoes in a one-week period is modeled by a Poisson distribution with mean 2
Three weeks, so [tex]\mu = 2*3 = 6[/tex]
Calculate the probability that fewer than four tornadoes occur in a three-week period.
This is:
[tex]P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3)[/tex]
In which
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
[tex]P(X = 0) = \frac{e^{-6}*6^{0}}{(0)!} = 0.0025[/tex]
[tex]P(X = 1) = \frac{e^{-6}*6^{1}}{(1)!} = 0.0149[/tex]
[tex]P(X = 2) = \frac{e^{-6}*6^{2}}{(2)!} = 0.0446[/tex]
[tex]P(X = 3) = \frac{e^{-6}*6^{3}}{(3)!} = 0.0892[/tex]
Then
[tex]P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) = 0.0025 + 0.0149 + 0.0446 + 0.0892 = 0.1512[/tex]
0.1512 = 15.12% probability that fewer than four tornadoes occur in a three-week period.
If 2(x + 3) - 27 = 3[7 - 2(x + 19)], what is 2x - 5?
Answer:
D = -23
Step-by-step explanation:
Answer:
D) -23
Step-by-step explanation:
Definitely
You buy a six pack of Gatorade for $9.00. What is the unit price or the price per bottle?
$1.50/bottle
$2/bottle
$1.75 per bottle
Answer:
The answer is $1.50/bottle.
Step-by-step explanation:
To get the unit price, you need to divide the total by the amount of bottles.
[tex]9.00/6=1.50[/tex]
answer quick it's urgent
Expand : (5xy+7)(5xy-7)
Answer:
[tex](5xy + 7)(5xy-7) = 25x^2 y^2 - 49[/tex]
Step-by-step explanation:
[tex](a - b)(a +b ) = a^2 - b^2 \\\\From \ given \ expression \ a = 5xy \ , \ b = 7\\\\Therefore , (5xy + 7 )(5xy - 7 ) = ( 5xy)^2 - ( 7)^2 \\[/tex]
[tex]= 25x^2 y^2 - 49[/tex]
Answer:
25x²y² - 49
Step-by-step explanation:
We can do this by using the a+b formula:
(a+b)(a-b)= a² - b²
So,
(5xy+7)(5xy-7)
=(5xy)² - 7²
= 25x²y² - 49
Another way we can do this by expanding the algebraic expression:
(5xy+7)(5xy-7)
= 5xy(5xy-7) + 7(5xy-7)
= 25x²y² - 35xy + 35xy - 49
= 25x²y²- 49
Find the slope of the line that passes through the two points 2,-4 & 4,-1
Answer:
Step-by-step explanation:
I have this saved on my computer in notepad b/c this type of question get asked sooo often :/
point P1 (-4,-2) in the form (x1,y1)
point P2(3,1) in the form (x2,y2)
slope = m
m = (y2-y1) / (x2-x1)
My suggestion is copy that above and save it on your computer for questions like this
now use it
Point 1 , P1 = (2,-4) in the form (x1,y1)
Point 2 , P2 = (4,-1) in the form (x2,y2)
m = [ -1-(-4) ] / [ 4-2]
m = (-1+4) / 2
m = 3 / 2
so now we know the slope is 3/2 :)
Is it possible to have a relation on the set {a, b, c} that is both symmetric and transitive but not reflexive
Answer:
Yes, it is possible to have a relation on the set {a, b, c} that is both symmetric and transitive but not reflexive
Step-by-step explanation:
Let
Set A={a,b,c}
Now, define a relation R on set A is given by
R={(a,a),(a,b),(b,a),(b,b)}
For reflexive
A relation is called reflexive if (a,a)[tex]\in R[/tex] for every element a[tex]\in A[/tex]
[tex](c,c)\notin R[/tex]
Therefore, the relation R is not reflexive.
For symmetric
If [tex](a,b)\in R[/tex] then [tex](b,a)\in R[/tex]
We have
[tex](a,b)\in R[/tex] and [tex](b,a)\in R[/tex]
Hence, R is symmetric.
For transitive
If (a,b)[tex]\in R[/tex] and (b,c)[tex]\in R[/tex] then (a,c)[tex]\in R[/tex]
Here,
[tex](a,a)\in R[/tex] and [tex](a,b)\in R[/tex]
[tex]\implies (a,b)\in R[/tex]
[tex](a,b)\in R[/tex] and [tex](b,a)\in R[/tex]
[tex]\implies (a,a)\in R[/tex]
Therefore, R is transitive.
Yes, it is possible to have a relation on the set {a, b, c} that is both symmetric and transitive but not reflexive.
Which of the following is the intersection of the line AD and line DE?
Answer:
Point D
Step-by-step explanation:
The intersection(s) of lines represents where they cross or intersect. We can see that lines AD and DE cross or intersect as Point D, hence the answer being Point D.
Answer: Point D
Step-by-step explanation: The intersection of two figures is the set of points that is contained in both figures. In the diagram shown, D is the intersection of lines AD and DE because D is the point contained by both line AD and DE.
Hello, please help me!!
Answer:
0.14
Step-by-step explanation:
P(A|B) asks for the probability of A, given that B has happened. This is equal to the probability of A and B over the probability of B (see picture)
Here, the question is asking if someone is taking the bus given that they are a senior.
The probability of someone being a senior and taking the bus is 5/100, or 0.05 . The probability of someone being a senior is 35/100, or 0.35
Our answer is then 0.05/0.35 = 1/7 = 0.14
Consider this linear function:
y = 1/2x + 1
Plot all ordered pairs for the values in the domain.
D: {-8, -4,0, 2, 6)
9514 1404 393
Answer:
see attached
Step-by-step explanation:
The attachment shows the ordered pairs (x, f(x)) and their graph.
Translate the sentence into an inequality. The product of w and 2 is less than 23.
Answer:
2w<23
Step-by-step explanation:
The product of w and 2 mean that w multiplied by 2
using the 1 to 9 at the most time each, fill in the boxes to make a true statement
Answer:
2
Step-by-step explanation:
8*8 is 64
Since it looks like the empty box is an exponent, and there are 2 8s being multiplied, the answer is 2
Can someone help me with this question an my other work?
Sarah ordered 39 shirts that cost $8 each. She can sell each shirt for $16.19. She sold 32 shirts to customers. She had to return 7 shirts and pay a $1.4 charge for each returned shirt. Find Sarah's profit.
Answer:
$196.28
Step-by-step explanation:
Original cost: 39 × $8 = $312
Revenue: 32 × $16.19 = $518.08
Return charge: 7 × $1.4 = $9.8
$312 + $9.8 = total cost, which is $321.8
$518.08 - $321.8 = profit
Profit = $196.28
If X is a normal random variable with mean 6 and standard deviation 2.0, then find the value x such that P(X > x) is equal to .7054. Group of answer choices5.28
5.46
4.92
7.28
Answer:
Step-by-step explanation:
If X is a normal random variable with a mean of 6 and a standard deviation of 3.0, then find the value x such that P(Z>x)is equal to .7054.
-----
Find the z-value with a right tail of 0.7054
z = invNorm(1-0.7054) = -0.5400
x = zs+u
x = -5400*3+6 = 4.38
Paul writes newspaper articles. He earns a base rate of $500 per month and an additional $100 per article he writes. Last month he earned $2000.
Write an equation to determine the number of articles (a) he sold last month.
Answer:
Total earning last month with x articles is:
x*100 + 500This is same amount as 2000
The equation is:
100x + 500 = 2000The principle of redundancy is used when system reliability is improved through redundant or backup components. Assume that a student's alarm clock has a 15.3% daily failure rate. Complete parts (a) through (d) below. a. What is the probability that the student's alarm clock will not work on the morning of an important final exam?
Answer:
[tex]Pr = 0.153[/tex]
Step-by-step explanation:
Given
[tex]p = 15.3\%[/tex]
Required
Probability of alarm not working
[tex]p = 15.3\%[/tex] implies that the alarm has a probability of not working on a given day.
So, the probability that the alarm will not work on an exam date is:
[tex]Pr = 15.3\%[/tex]
Express as decimal
[tex]Pr = 0.153[/tex]
The cost of 5 gallons of ice cream has a variance of 64 with a mean of 34 dollars during the summer. What is the probability that the sample mean would differ from the true mean by less than 1.1 dollars if a sample of 38 5-gallon pails is randomly selected
Answer:
0.5587 = 55.87% probability that the sample mean would differ from the true mean by less than 1.1 dollars.
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 establishes 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.
The cost of 5 gallons of ice cream has a variance of 64 with a mean of 34 dollars during the summer.
This means that [tex]\sigma = \sqrt{64} = 8, \mu = 34[/tex]
Sample of 38
This means that [tex]n = 38, s = \frac{8}{\sqrt{38}}[/tex]
What is the probability that the sample mean would differ from the true mean by less than 1.1 dollars ?
P-value of Z when X = 34 + 1.1 = 35.1 subtracted by the p-value of Z when X = 34 - 1.1 = 32.9. So
X = 35.1
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{35.1 - 34}{\frac{8}{\sqrt{38}}}[/tex]
[tex]Z = 0.77[/tex]
[tex]Z = 0.77[/tex] has a p-value of 0.77935
X = 32.9
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{32.9 - 34}{\frac{8}{\sqrt{38}}}[/tex]
[tex]Z = -0.77[/tex]
[tex]Z = -0.77[/tex] has a p-value of 0.22065
0.77935 - 0.22065 = 0.5587
0.5587 = 55.87% probability that the sample mean would differ from the true mean by less than 1.1 dollars.
a woman bought some large frames for
$12 each and some small frames for $5
each. If she bought 20 frames for $156
find how many of each type she bought.
Answer:
8 pairs of large glasses and 12 pairs of small ones
Step-by-step explanation:
Let's say the number of large frames she buys is l, and the number of small frames is s. She buys 20 frames of assorted sizes, but they can only be small or large. Therefore, s + l = 20.
Next, the total cost of large frames is 12 dollars for each frame. Therefore, the total cost for the large frames is equal to 12 * l. Similarly, the total cost for the small frames is equal to 5 * s. The total cost of all frames is equal to 156, so
12* l + 5 * s = 156
s + l = 20
In the second equation, we can subtract l from both sides to get
s = 20 - l
We can then plug that into the first equation to get
12 * l + 5 * (20-l) = 156
12 * l + 100 - 5*l = 156
subtract both sides by 100 to isolate the variable and its coefficient
12 * l - 5 * l = 56
7 * l = 56
divide both sides by 7 to isolate the l
l = 8
The woman buys 8 pairs of large glasses. The number of small glasses is equal to 20-l=20-8=12
please help to solve this in written format
Answer:
50 dozen total
Step-by-step explanation:
8/12 & 10/12.... average 9/12
11/12 - 9/12 =
2/12x = 100
2x = 1200
x = 600/12
50 dozen total
Using law of sines please show process!!!
Let the <C=x
We know in a triangle
☆Sum of angles=180°
[tex]\\ \sf\longmapsto 51+26+x=180[/tex]
[tex]\\ \sf\longmapsto 77+x=180[/tex]
[tex]\\ \sf\longmapsto x=180-77[/tex]
[tex]\\ \sf\longmapsto x=103°[/tex]
