Answer:
3 hour: electrician B because you would save $15
8 hour: electrician A because you would save $10
Step-by-step explanation:
35×3+100=205 vs 40×3+70=190
b is 15 dollars less
35×8+100=380 vs 40×3+70=390
a is 10 dollars less
Evaluate the expression when a = 6 and x = -3.
-a+7x
Answer:
-27
Step-by-step explanation:
The equation -a+7x, when plugged in shows -6+7*(-3).
This gives us -6-21 which is -27.
By the way can you follow me on Brainly?
Thanks!
can someone help me on this?
Answer:
Step-by-step explanation:
The National Assessment of Educational Progress (NAEP) includes a "long-term trend" study that tracks reading and mathematics skills over time, and obtains demographic information. In the 2012 study, a random sample of 9000 17-year-old students was selected.24 The NAEP sample used a multistage design, but the overall effect is quite similar to an SRS of 17-year-olds who are still in school. In the sample, 51% of students had at least one parent who was a college graduate. Estimate, with 99% confidence, the proportion of all 17-year-old students in 2012 who had at least one parent graduate from college.
Answer:
The 99% confidence interval estimate for the proportion of all 17-year-old students in 2012 who had at least one parent graduate from college is (0.4964, 0.5236).
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].
Sample of 9000, 51% of students had at least one parent who was a college graduate.
This means that [tex]n = 9000, \pi = 0.51[/tex]
99% confidence level
So [tex]\alpha = 0.01[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.51 - 2.575\sqrt{\frac{0.51*0.49}{9000}} = 0.4964[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.51 + 2.575\sqrt{\frac{0.51*0.49}{9000}} = 0.5236[/tex]
The 99% confidence interval estimate for the proportion of all 17-year-old students in 2012 who had at least one parent graduate from college is (0.4964, 0.5236).
The diameter of a cake is 7.8 inches. What is the area of the cake?
Answer:
A = 12.25 sq inches
Step-by-step explanation:
A = (7.8/2)²π
A = 3.9²π
A = 12.25 sq inches
The length of a rectangular swimming pool is exactly three times as long
as its width. If the pool has a perimeter of 472m find the width of the pool
Answer:
59m
Step-by-step explanation:
Length= 3 × ( width)
But perimeter= 2width + 2 Lenght= 472
Let length= X
Width= Y
X= 3Y.........eqn(1)
2X + 2Y= 472........eqn(2)
Substitute X= 3Y in eqn(2)
2(3Y) + 2Y = 472
6Y + 2Y= 472
8Y= 472
Y= 59 m
Hence, the width of the pool is 59 m
Don uses a funnel to pour oil into his car engine. The funnel has a radius of 6 cm and a slant height of 10 cm. How much oil, to the nearest cubic centimeter, will the funnel hold.
look at pic 10 pts will mark brainilest
Answer:
A) The width is 12 cm; the average time is 3 minutes
Step-by-step explanation:
[tex]\frac{5}{3}= \frac{20}{y}[/tex]
Cross multiply.
5 × y = 3 × 20
5y = 60
5y ÷ 5 = 60 ÷ 5
y = 12
The width is 12 cm. Moving onto the time.
[tex]\frac{12}{4} =\frac{y}{1}[/tex]
Cross multiply.
4 × y = 12 × 1
4y = 12
4y ÷ 4 = 12 ÷ 4
y = 3
The time is 3 minutes.
Answer:
answer is d sorry if I'm wrong
solve For X if 9( x²_1 )= 27 x 2187
Answer:
use photomath it'll slove it for you
Step-by-step explanation:
Apply the distributive property to create an equivalent expression. 6 ( a + 2 b + 3 c ) =
Answer: 6
Step-by-step explanation: a + 2b + 3 c = a + 2b + 3c
I need help ASAP i will give brainlist
Answer:
M
Step-by-step explanation:
Answer:
Point M
Step-by-step explanation:
Each line represents 0.05 so M would best represent 1/3
A worldwide organization of academics claims that the mean IQ score of its members is 118, with a standard deviation of 17. A randomly selected group of 40 members of this organization is tested, and the results reveal that the mean IQ score in this sample is 115.8. If the organization's claim is correct, what is the probability of having a sample mean of 115.8 or less for a random sample of this size
Answer:
0.2061 = 20.61% probability of having a sample mean of 115.8 or less for a random sample of this size
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 estabilishes 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.
A worldwide organization of academics claims that the mean IQ score of its members is 118, with a standard deviation of 17.
This means that [tex]\mu = 118, \sigma = 17[/tex]
A randomly selected group of 40 members
This means that [tex]n = 40, s = \frac{17}{\sqrt{40}} = 2.6879[/tex]
What is the probability of having a sample mean of 115.8 or less for a random sample of this size?
This is the pvalue of Z when X = 115.8.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{115.8 - 118}{2.6879}[/tex]
[tex]Z = -0.82[/tex]
[tex]Z = -0.82[/tex] has a pvalue of 0.2061
0.2061 = 20.61% probability of having a sample mean of 115.8 or less for a random sample of this size
Hi I need ur help! (And this is the other one if you saw my last question)
Answer:
Hi gimmie brainly
thanks
A family spends 1/10 of it's annual income for housing 1/4 for food and clothing 1/5 for general expenses and 2/15 for entertainment what fractional part of their income is spent on these items altogether.
Answer:
The family spends 41/60 of its income on these items altogether.
Step-by-step explanation:
Given that a family spends 1/10 of it's annual income for housing, 1/4 for food and clothing, 1/5 for general expenses and 2/15 for entertainment, to determine what fractional part of their income is spent on these items altogether the following calculation must be performed:
10, 4, 5, and 15 have a common least multiple at 60.
1/10 = 6/60
1/4 = 15/60
1/5 = 12/60
2/15 = 8/60
6 + 15 + 12 + 8 = 41
Therefore, the family spends 41/60 of its income on these items altogether.
Which of the following is closest to the mean absolute deviation of this
data set: 2.1, 3.5, 4.6, 5.8, 3.9, 4.2, 2.8?
A. 0.89
B. 1.6
C. 3.84
D. 3.9
Answer:
0.89
Step-by-step explanation:
Trust
Will give brainliest for correct answer
Answer:
A function is a rule that assigns to each input exactly one output.
Step-by-step explanation:
If you have more than one of the same inputs for multiple outputs, it would create a vertical line at somepoint on your line.
Answer:
The correct answer is "a rule that assigns to each input exactly one output".
Step-by-step explanation:
In mathematics, a function is a binary relation between two sets that associates to each element of the first set exactly one element of the second set. Typical examples are functions from integers to integers, or from real numbers to real numbers.
Factor the binomial b^2 - 9
Answer:
(b-3)(b+3)
Step-by-step explanation:
b^2+3b-3b-9
Wayne Gretsky scored a Poisson mean six number of points per game. sixty percent of these were goals and forty percent were assists (each is worth one point). Suppose he is paid a bonus of 3K for a goal and 1K for an assist. (a) Find the mean and standard deviation for the total revenue he earns per game. (b) What is the probability that he has four goals and two assists in one game
Answer:
a) The mean for the total revenue he earns per game is of 13.2K while the standard deviation is of 3.63K.
b) 0.05 = 5% probability that he has four goals and two assists in one game
Step-by-step explanation:
In hockey, a point is counted for each goal or assist of the player.
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. The standard deviation is the square root of the mean.
(a) Find the mean and standard deviation for the total revenue he earns per game.
60% of six are goals, which means that 60% of the time he earned 3K.
40% of six are goals, which means that 40% of the time he earned 1K.
The mean is:
[tex]\mu = 6*0.6*3 + 6*0.4*1 = 13.2[/tex]
The standard deviation is:
[tex]\sigma = \sqrt{\mu} = \sqrt{13.2} = 3.63[/tex]
The mean for the total revenue he earns per game is of 13.2K while the standard deviation is of 3.63K.
(b) What is the probability that he has four goals and two assists in one game
Goals and assists are independent of each other, which means that we find the probability P(A) of scoring four goals, the probability P(B) of getting two assists, and multiply them.
Probability of four goals:
60% of 6 are goals, which means that:
[tex]\mu = 6*0.6 = 3.6[/tex]
The probability of scoring four goals is:
[tex]P(A) = P(X = 4) = \frac{e^{-3.6}*(3.6)^{4}}{(4)!} = 0.19122[/tex]
Probability of two assists:
40% of 2 are assists, which means that:
[tex]\mu = 6*0.4 = 2.4[/tex]
The probability of getting two assists is:
[tex]P(B) = P(X = 2) = \frac{e^{-2.4}*(2.4)^{2}}{(2)!} = 0.26127[/tex]
Probability of four goals and two assists:
[tex]P(A \cap B) = P(A)*P(B) = 0.19122*0.26127 = 0.05[/tex]
0.05 = 5% probability that he has four goals and two assists in one game
Can someone please help me with Systems of Equation. If so please comment here and friend me at fmilluzionz#1521. I am in 8th grade math
Answer:
The FitnessGram PACER Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The test is used to measure a student's aerobic capacity as part of the FitnessGram assessment. Students run back and forth as many times as they can, each lap signaled by a beep sound.
Step-by-step explanation:
Which of the following lists of fractions are in order from least to greatest? Select TWO that apply.
A.
1/4 2/3 3/10
B.
3/5 7/10 5/6
C.
2/5 5/8 3/4
D.
3/8 9/10 7/12
HELP
Answer:
i think its a 1/4 then 2/3 and 3/10
Find the range of the data
5,9,13,6,4,5,8,12,12,6
Answer:
9
Step-by-step explanation:
highest value: 13
lowest value: 4
13-4= 9 which is the range
Answer: 9
Step-by-step explanation: 13-4=9
Seamus draws a triangle with angles of measures 40°, 60°, and 80°. Edwina draws a triangle with these same three angle measures. Which statement must be true?
A Edwina's triangle is the same size as Seamus's triangle.
B Edwina's triangle is the same shape as Seamus's triangle.
C The perimeter of Seamus's triangle is greater than the perimeter of Edwina's triangle.
D The area of Edwina's triangle is less than the area of Seamus's triangle.
Answer:
It may be D or A hopeit helps
Step-by-step explanation:
the function f(x) = -x^2 + 44x -384 models the daily profit in dollars that a shop makes
Which one of the following U.S. customary units is closest in volume to I liter?
Answer:
c
Step-by-step explanation:
Quart is one of the following U.S. customary units is closest in volume to 1 liter. Option D is correct.
What is volume?The term "volume" refers to the amount of three-dimensional space taken up by an item or a closed surface. It is denoted by V and its SI unit is in cubic cm.
The relation between the quart and the liter is found as;
1 quarts = 0.94635295 liters
The value in liter is approximately equal to 1. Quart is one of the following U.S. customary units is closest in volume to 1 liter.
Hence,option D is correct.
To learn more about the volume refer:
https://brainly.com/question/1578538
#SPJ2
Find the equation of the line shown. Enter yoir answwr in slope intercept form
Answer:
y = x
Step-by-step explanation:
The equation for slope is y = mx +b. If you look at the line you see that it passes through the origin, this is your y-intercept, 0. If you look at two points at the line and use the rise over run method, you get the slope to be 1. If you substituent these values into the equation you get, y = x.
Hope this helps!
-Luna
Fast Auto Service provides oil and lube service for cars. It is known that the mean time taken for oil and lube service at this garage is 15 minutes per car and the standard deviation is 2.4 minutes. The management wants to promote the business by guaranteeing a maximum waiting time for its customers. If a customer's car is not serviced within that period, the customer will receive a 50% discount on the charges. The company wants to limit this discount to at most 8% of the customers. What should the maximum guaranteed waiting time be
Answer:
The maximum guaranteed waiting time should be of 18.37 minutes.
Step-by-step explanation:
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.
It is known that the mean time taken for oil and lube service at this garage is 15 minutes per car and the standard deviation is 2.4 minutes.
This means that [tex]\mu = 15, \sigma = 2.4[/tex]
The company wants to limit this discount to at most 8% of the customers. What should the maximum guaranteed waiting time be?
The 100 - 8 = 92th percentile, which is X when Z has a pvalue of 0.92. So X when Z = 1.405.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]1.405 = \frac{X - 15}{2.4}[/tex]
[tex]X - 15 = 1.405*2.4[/tex]
[tex]X = 18.37[/tex]
The maximum guaranteed waiting time should be of 18.37 minutes.
How do you write 5.09 104 in standard form?
5. Consider kite HIJK. If HK = 8 and HP = 5, find KP.
H
К.
Р
Answer:
Step-by-step explanation:
KP²+HP²=KH²
KP²+5²=8²
KP²=64-25=39
KP=√39
Milo is working on a wall mural using geometric shapes. The mural includes parallelograms and rectangles like the ones below.
Opposite sides are parallel.
Opposite sides are congruent.
Opposite angles are congruent.
Opposite angles are right angles.
Answer:
Opposite angles are right angles.
Step-by-step explanation:
A circle has a radius of 5 centimeters. What is its area?
Answer:
[tex] \bf \huge 78.5 \: c.m.[/tex]
Step-by-step explanation:
Given that :A circle has a radius of 5 centimeters. to find :What is its area?formulas used :A = πr²where,
A = areaπ = 22/7 r = radiusexplanation :finding the area of circle
⟼ A = πr²
⟼ A = 22/7 × 5²
⟼ A = 22/7 × 5 × 5
⟼ A = 3•14 × 5 × 5
⟼ A = 3•14 × 25
⟼ A = 78•5
∴ the area of circle is 78•5 centimeters
A picture is to be printed onto a sheet of paper with dimensions of 81/2 x 11 inches, A margin of 1 1/2 inches is to be left on all sides of the picture. What is the area of the printed picture?
Answer:
The area of the printed picture is 172.5 square inches.
Step-by-step explanation:
Since a picture is to be printed onto a sheet of paper with dimensions of 81/2 x 11 inches, and a margin of 1 1/2 inches is to be left on all sides of the picture, to determine what is the area of the printed picture the following calculation must be carried out, knowing that the area of a rectangle is equal to the base multiplied by the height:
81/2 = 40.5
1/2 = 0.5
40.5 - 1.5 x 4 = 34.5
11 - 1.5 x 4 = 5
34.5 x 5 = 172.5
Therefore, the area of the printed picture is 172.5 square inches.
