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
Allisa [31]
3 years ago
10

The length of a rectangle is four times it’s width. of the width is 15, what is the area?

Mathematics
1 answer:
zheka24 [161]3 years ago
6 0

Answer: A=900

The awnser is 900


Step-by-step explanation:

15 x 4 = 60 60 x 15 equals 900

You might be interested in
Calcium is essential to tree growth because it promotes the formation of wood and maintains cell walls. In 2010, the concentrati
sergij07 [2.7K]

Answer:

The p-value obtained from the hypothesis test is greater than the significance level at which the test was performed, hence, we fail to reject the null hypothesis & say that there isn't enough evidence from the sample to conclude that the the calcium concentrations have changed since 2010.

Step-by-step explanation:

To perform this test, we need to first obtain the sample mean and sample standard deviation.

The data is 0.065 0.087 0.070 0.262 0.126 0.183 0.120 0.234 0.313 0.108

Mean = (sum of variables)/(sample size)

= (0.065+0.087+0.070+0.262+0.126+0.183+0.120+0.234+0.313+0.108)/10

= 0.1568 milligram per liter

Standard deviation = σ = √[Σ(x - xbar)²/N]

Σ(x - xbar)² = 0.00842724+0.00487204+0.00753424+0.01106704+0.00094864+0.00068644+0.00135424+0.00595984+0.02439844+0.00238144

= 0.0676296

σ = √[Σ(x - xbar)²/N] = √(0.0676296/10) = 0.08224 milligrams per liter

To do an hypothesis test, we need to first define the null and alternative hypothesis

The null hypothesis plays the devil's advocate and usually takes the form of the opposite of the theory to be tested. It usually contains the signs =, ≤ and ≥ depending on the directions of the test.

While, the alternative hypothesis usually confirms the the theory being tested by the experimental setup. It usually contains the signs ≠, < and > depending on the directions of the test.

For this question, the null hypothesis would be that there is no significant evidence to suggest that the the calcium concentrations have changed since 2010. That is, the calcium concentrations haven't changed since 2010.

The alternative hypothesis is that there is significant evidence to suggest that the the calcium concentrations have changed since 2010. That is, the calcium concentrations haven't changed since 2010.

Mathematically,

The null hypothesis is represented as

H₀: μ = 0.11 milligrams per liter

The alternative hypothesis is given as

Hₐ: μ ≠ 0.11 milligrams per liter

To do this test, we will use the t-distribution because no information on the population standard deviation is known

So, we compute the t-test statistic

t = (x - μ₀)/σₓ

x = sample mean = 0.1568 milligram per liter

μ₀ = the mean calcium concentrations from 2010 = 0.11 milligrams per liter

σₓ = standard error = (σ/√n)

where n = Sample size = 10

σ = Sample standard deviation = 0.08224 milligrams per liter

σₓ = (σ/√n) = (0.08224/√10) = 0.026

t = (0.1568 - 0.11) ÷ 0.026

t = 1.80

checking the tables for the p-value of this t-statistic

Degree of freedom = df = 10 - 1 = 10 - 1 = 9

Significance level = 0.05

The hypothesis test uses a two-tailed condition because we're testing in two directions. (Greater than and less than)

p-value (for t = 1.80, at 0.05 significance level, df = 9, with a two tailed condition) = 0.105391

The interpretation of p-values is that

When the (p-value > significance level), we fail to reject the null hypothesis and when the (p-value < significance level), we reject the null hypothesis and accept the alternative hypothesis.

So, for this question, significance level = 0.05

p-value = 0.105391

0.105391 > 0.05

Hence,

p-value > significance level

This means that we fail to reject the null hypothesis & say that there isn't enough evidence to conclude that the the calcium concentrations have changed since 2010.

Hope this Helps!!!

8 0
3 years ago
The first gardener can finish the job in 6 hours, and the second gardener can do the same job in 7 hours. How long it will take
marissa [1.9K]

If the first gardener can finish the job in 6 hours, it means that every hour he completes 1/6 of the job.

By the same logic, the second gardener completes 1/7 of the job per hour.

So, if they work together, they complete

\dfrac{1}{6}+\dfrac{1}{7}=\dfrac{7+6}{42}=\dfrac{13}{42}

of the job per hour.

So, after 42/13 of a hour, they'll complete the job. Since one hour is made of 60 minutes, 42/13 of a hour is

\dfrac{42}{13}\cdot 60 \approx 194

So, it will take them about 194 minutes to finish the job, i.e. about 3 hours and 14 minutes.

8 0
3 years ago
Help!!!! for just 3 but if you know 4 also then it’s on my page and I would appreciate the help
Rus_ich [418]
A quadratic equation is set up in the form of ax² + bx +c
First set equation = to 0
0= x² - 5x - 24
Next plug into quadratic formula( -b Plus or minus the √b²-4ac) ÷ 2a
[10 plus or minus √(25² - 4×1×24)] ÷ 2
Solve for inner parenthesis first 
√625- 96   = √529
Now set up two equations
(10 + √529) ÷2   = x   = 16.5
(10 -  √529) ÷2   = x   = -6.5 
So therefore x = 16.5 and -6.5



8 0
3 years ago
A
GREYUIT [131]
The answer is D. First, it is the segment addition postulate because the two segments make up the whole. Second, it's substitution because you are substituting EF + FG for FH.

Hope this helps!
8 0
3 years ago
Read 2 more answers
a college student needs 11 classes that are worth a total of 40 credits in order to complete her degree. The college offers both
Rasek [7]
I’m not entirely sure but I think it’s D
8 0
2 years ago
Other questions:
  • Wha are true statements about a 30-60-90 triangle
    9·1 answer
  • On a coordinate plane, a triangle has points A prime (1, 2), B prime (3, negative 3), C prime (negative 1, negative 3). Triangle
    7·2 answers
  • Help me please I need this for tomorrow <br> Questions:24,25,26 and 27 please<br> and Godbless you
    7·1 answer
  • PLEASE HELP!!!
    7·1 answer
  • Kelly walks .7 miles to school Mary walks .49 miles to school write an equation using greater than less than or equal to to comp
    14·2 answers
  • A number p multiplied by -4 is no more than 12 how do you put that as an equation?
    9·1 answer
  • I need help plsss ;(((
    8·1 answer
  • 50 POINTS
    10·2 answers
  • X
    12·1 answer
  • Which answer best describes the complex zeros of the polynomial function? f(x)=x3+x2+10x+10
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!