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
lozanna [386]
3 years ago
7

A 9-foot piece of wood is cut into shelves. If each is 3/7 foot in length, how many shelves are there?

Mathematics
1 answer:
Aloiza [94]3 years ago
6 0

Hello!

To find how much shelves we cut, we need to divide 9 feet by 3/7 feet. When dividing by fractions, it is like multiplying its reciprocal.

This means that the reciprocal of 3/7 is 7/3.

9 / \frac{3}{7} = \frac{9}{1} * \frac{7}{3} = \frac{63}{3} = 21

Therefore, if each shelf is 3/7 feet in length, then there are 21 shelves.

You might be interested in
A company with a large fleet of cars wants to study the gasoline usage. They check the gasoline usage for 50 company trips chose
Nookie1986 [14]

Answer:

The 95% confidence interval is given by (25.71536 ;28.32464)

And if we need to round we can use the following excel code:

round(lower,2)

[1] 25.72

round(upper,2)

[1] 28.32

And the interval would be (25.72; 28.32)  

Step-by-step explanation:

Notation and definitions  

n=50 represent the sample size  

\bar X= 27.2 represent the sample mean  

s=5.83 represent the sample standard deviation  

m represent the margin of error  

Confidence =88% or 0.88

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".  

The margin of error is the range of values below and above the sample statistic in a confidence interval.  

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".  

Calculate the critical value tc  

In order to find the critical value is important to mention that we don't know about the population standard deviation, so on this case we need to use the t distribution. Since our interval is at 88% of confidence, our significance level would be given by \alpha=1-0.88=0.12 and \alpha/2 =0.06. The degrees of freedom are given by:  

df=n-1=50-1=49  

We can find the critical values in R using the following formulas:  

qt(0.06,49)

[1] -1.582366

qt(1-0.06,49)

[1] 1.582366

The critical value tc=\pm 1.582366  

Calculate the margin of error (m)  

The margin of error for the sample mean is given by this formula:  

m=t_c \frac{s}{\sqrt{n}}  

m=1.582366 \frac{5.83}{\sqrt{50}}=14.613  

With R we can do this:

m=1.582366*(5.83/sqrt(50))

m

[1] 1.304639

Calculate the confidence interval  

The interval for the mean is given by this formula:  

\bar X \pm t_{c} \frac{s}{\sqrt{n}}  

And calculating the limits we got:  

27.02 - 1.582366 \frac{5.83}{\sqrt{50}}=25.715  

27.02 + 1.582366 \frac{5.83}{\sqrt{50}}=28.325

Using R the code is:

lower=27.02-m;lower

[1] 25.71536

upper=27.02+m;upper

[1] 28.32464

The 95% confidence interval is given by (25.71536 ;28.32464)  

And if we need to round we can use the following excel code:

round(lower,2)

[1] 25.72

round(upper,2)

[1] 28.32

And the interval would be (25.72; 28.32)  

6 0
3 years ago
Our football team won 3/4 of the game that you played it was 12 games how many games did it play
Katen [24]

Answer:

24

Step-by-step explanation:

4 0
3 years ago
A scientist measured the water pressure at different depths. She made a table showing her findings. The x-values represent the d
inessss [21]

Answer:

100,70 is the answer I took the test

5 0
3 years ago
A Polynomial Identity is True when you work the problem out and both sides are equal to each other
USPshnik [31]

answer

it is true

step by step explanation

4 0
2 years ago
Coffee beans are packaged in 50 kg cartons with an allowable error of 0.7% What is the acceptable weight range for a carton of c
goldfiish [28.3K]
0.35, you multiply 50 times 0.7%
6 0
3 years ago
Read 2 more answers
Other questions:
  • Solve each system by substitution.
    11·1 answer
  • Which expression is the LCD of these functions? 1/p^3 and 4/7? PLEASE HELP??!?!?!?!?!?!??!?!?!?!?!??!?!?!?!?!?!?!??!?!
    15·1 answer
  • SOMEONE ANY BOY HELP PLZ!!! PLZ!!! PLZ!!! WILL GIVE BRAINLIEST IS ANSWER RIGHT
    15·1 answer
  • 3/4 Multiply 2/7 simplest form
    10·2 answers
  • Solve by substitution<br><br>3x - 3y = -6 <br><br> z=-3x-3y+9<br><br> -4x+5y+z=8
    8·1 answer
  • How many factors of 10 are in 1,000
    6·2 answers
  • Write the equation of the line in fully simplified slope-intercept form.​
    7·1 answer
  • 2(3x + 2) = 2x - 1+x.
    7·2 answers
  • Evaluate each using the values given.<br> 7) 3 - x + x + y; use x = 4, and y=-1
    12·1 answer
  • Solve the simultaneous equation<br> 3x + y = 8<br> x - 3y = 11
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!