1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
algol13
3 years ago
14

A study of the amount of time it takes a mechanic to rebuild the transmission for a 2005 Chevrolet Cavalier shows that the mean

is 8.4 hours and the standard deviation is 1.8 hours. If 40 mechanics are randomly selected, find the probability that their mean rebuild time exceeds 8.7 hours.
0.1346

0.1285

0.1946

0.1469
Mathematics
1 answer:
iogann1982 [59]3 years ago
3 0

Answer:

0.1469

Step-by-step explanation:

Given from the question;

Mean=8.4 hrs=μ

Standard deviation=1.8 hrs=δ

Sample size, n=40

Let  x=8.7

z=(x-μ)÷(δ÷√n)  

Find z(8.7)

z=(8.7-8.4)÷(1.8÷√40)

z={0.3×√40}÷1.8=1.05409

z=1.0541

Read from the  standard normal probabilities table

P(z>1.0541)

=0.1459

You might be interested in
In order to compare the real estate markets in Pittsburgh and Philadelphia, a realtor selected
melisa1 [442]

Answer:

The price of the homes in the Pittsburgh sample typically vary by about $267,210 from the mean home price of $500,000.

Step-by-step explanation:

The dotplots reveal that the variability of home prices in the Pittsburgh sample is greater than the variability of home prices in the Philadelphia sample. Therefore, the standard deviation of the home prices for the Pittsburgh sample is $267,210 rather than $100,740. The correct interpretation of this statistic is that the price of homes in Pittsburgh typically vary by about $267,210 from the mean home price of $500,000.

5 0
2 years ago
Solve the equation 2x^2 + 4x - 39 to the nearest tenth.
Virty [35]

Answer:

cant be solved, when you try to you get

-1+78 = 77

which is

77 = 77

1=1

So cannot be factored

Step-by-step explanation:

8 0
2 years ago
Simplify the expression. <br><br> ( I got 144, but i'm not sure)
g100num [7]

Answer:

144 is correct

Step-by-step explanation:

13 - 1 is 12

12 times 12 = 144

144 divided by 2 is 72

72 times 2 is 144

8 0
3 years ago
Read 2 more answers
If you go out to eat with 3 friends and your meal was $72.50, there is 6.75% sales tax and you should tip the waiter 15%. How mu
zhuklara [117]

Answer:

$29.67

Step-by-step explanation:

first you would fin out how much the total would be with the sales tax( which is equal to $4.89) added to the initial cost which should add up to $77.39

the 15% tip would add $11.61 to the $77.39

divide 89 by 3 which should give you 29.67

6 0
2 years ago
Read 2 more answers
A real estate broker's base salary is $18,000. She earns a 4% commission on total sales. How much must she sell to earn $55,000
evablogger [386]

The salary of the real estate broker = $18,000

Commission earned on total sales = 4% or 0.04

Total income earnings = $55,000

Let the total sales be = x

Equation becomes :

18000+0.04x=55000

0.04x=55000-18000

0.04x=37000

x=925000

Hence, the real estate broker must sell $925,000 worth of real estate to earn $55,000.

6 0
3 years ago
Other questions:
  • Nick starts with 20 milligrams of a radioactive substance. The amount of the substance decreases by 12 each week for a number of
    12·1 answer
  • What is 150,000,000 in scientific notion, PLEASE answer asap im so far behind!!
    13·1 answer
  • 2 7/10 + 5/8 what is the answer
    6·2 answers
  • You spin the spinner shown below once. Each sector shown has an equal area.
    13·2 answers
  • In how many ways could nine people be divided into two groups of two people and one group of five people?
    8·1 answer
  • Which is the graph of the linear function that is represented by the equation y= 1/2x-2
    13·1 answer
  • Can someone please help me figure this out
    11·1 answer
  • King Soopers has two different sizes of sport drinks. Sigi wanted to make sure that he got the size with the better price. There
    11·1 answer
  • Which point represents the unit rate​
    7·2 answers
  • Rei bought 150 oranges and 100 apples for her neighbours. She divided the oranges equally among them and had 17 oranges left. Sh
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!