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
valkas [14]
3 years ago
8

What is 15% of 80 38 is what percent of 40

Mathematics
2 answers:
devlian [24]3 years ago
8 0

(a) 15% of 80 = 0.15 x 80 = 12


Answer (a) : 12


(b) 38/40 x 100% = 95%


Answer (b) : 95%

leva [86]3 years ago
5 0

1a) 80 * 0.15 = 12


1b) 38/40 * 100% = 95%

You might be interested in
Evaluate the expression √(-6)/(√(-9) √(-1)) and write the result in the form a+bi.
DaniilM [7]
√6/3√i
Let me know if you need work

3 0
3 years ago
< Exit
Roman55 [17]

Answer:

88m of fencing

Step-by-step explanation:

the cicumference of the garden is what we are looking out for,

and with the raduis .ie.14m

C=2πr

C=2•22/7•14

C=88m

8 0
3 years ago
Please help me Im confused on this problem
Sunny_sXe [5.5K]

Answer:

b = 6 sqrt(2)

Step-by-step explanation:

Since this is right triangle, we can use the Pythagorean theorem

a^2+b^2 = c^2  where a and b are the legs and c is the hypotenuse

3^2 + b^2 = 9^2

9+b^2 = 81

b^2 = 81-9

b^2 = 72

Take the square root of each side

sqrt(b^2) = sqrt(72)

b = sqrt(36*2)

b = 6 sqrt(2)

7 0
3 years ago
GRE Test: The Graduate Record Examination (GRE) is a test required for admission to many US graduate schools. Student’s scores o
Zepler [3.9K]

Answer:

a) \bar X=144.3

b) The 95% confidence interval would be given by (138.846;149.754)      

c) n=34

d) n=298

e) n=1190

Step-by-step explanation:

Previous concepts

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".

We can calculate the sample mean with this formula:

\bar X = \frac{\sum_{i=1}^n x_i}{n}

\bar X=144.3 represent the sample mean  

\mu population mean (variable of interest)

\sigma=8.8 represent the population standard deviation

n=10 represent the sample size  

a) Find a point estimate of the population mean

We can calculate the sample mean with this formula:

\bar X = \frac{\sum_{i=1}^n x_i}{n}

\bar X=144.3

b) Construct a 95% confidence interval for the true mean score for this population.

The confidence interval for the mean is given by the following formula:

\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}   (1)

Since the Confidence is 0.95 or 95%, the value of \alpha=0.05 and \alpha/2 =0.025, and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.025,0,1)".And we see that t_{\alpha/2}=1.96

Now we have everything in order to replace into formula (1):

144.3-1.96\frac{8.8}{\sqrt{10}}=138.846    

144.3+1.96\frac{8.8}{\sqrt{10}}=149.754

So on this case the 95% confidence interval would be given by (138.846;149.754)    

Part c

The margin of error is given by this formula:

ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}    (a)

And on this case we have that ME =+20 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

n=(\frac{z_{\alpha/2} \sigma}{ME})^2   (b)

The critical value for 95% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.025;0;1)", and we got z_{\alpha/2}=1.960, replacing into formula (5) we got:

n=(\frac{1.960(8.8)}{3})^2 =33.05 \approx 34

So the answer for this case would be n=34 rounded up to the nearest integer

Part d

n=(\frac{1.960(8.8)}{1})^2 =297.493 \approx 298

So the answer for this case would be n=298 rounded up to the nearest integer

Part e

n=(\frac{1.960(8.8)}{0.5})^2 =1189.97 \approx 1190

So the answer for this case would be n=1190 rounded up to the nearest integer

7 0
3 years ago
Whats the ninth term of 25 20 15 10 5
Kaylis [27]

Given:

The sequence is 25, 20, 15, 10, 5.

To find:

The ninth term of the given sequence.

Solution:

We have,

25, 20, 15, 10, 5

It is an AP because the difference between two consecutive terms are same.

Here,

First term (a) = 25

Common difference (d) = 20-25

                                       = -5

The nth terms of an AP is

a_n=a+(n-1)d

Where, a is the first term and d is the common difference.

Putting a=25, n=9 and d=-5 to get the 9th term.

a_9=25+(9-1)(-5)

a_9=25+(8)(-5)

a_9=25-40

a_9=-15

Therefore, the ninth term of the given sequence is -15.

3 0
2 years ago
Other questions:
  • Let f(x)=x+8and g(x)=x^2-6x-7. Find f(g(2))
    7·1 answer
  • Given abcd efgh what is the measure of h
    7·2 answers
  • 90% as a decimal rounded to the thousands place
    8·2 answers
  • "Quick question.
    14·2 answers
  • Expand ( p + 6 )( p - 3 )​
    11·2 answers
  • Anyone want to help me with math <br> Solve 1−2/5 &lt; 5x+2/5−4x
    13·1 answer
  • Which of the following terms is not a monomial
    12·1 answer
  • Please hurry 50 points for the correct answer!<br> Which locker has the larger capacity? Explain.
    6·2 answers
  • A crack in the Earth's crust
    8·2 answers
  • Solve the equation and enter the value of x below.<br> 8x + 11 = 35
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!