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
navik [9.2K]
3 years ago
10

On a math test, 30 students earned a B. This number is exactly 40% of the total number of students in the class. How many studen

ts are in the class
Mathematics
1 answer:
Tju [1.3M]3 years ago
4 0
There are 75 students in the class. 30*100/40=75
You might be interested in
Questions on file. Thx.<br>Pls number questions to answer
ZanzabumX [31]
Second one
1/16
3/8 divided by 1/6=1/16
3 0
3 years ago
Read 2 more answers
Add and simplify 1/5 + 1/10
aliya0001 [1]

In order to add these fractions we have to make a common denominator.

1/5 can turn into 2/10 Its the same thing. And its easier to solve with.

now lets multiply.

\frac{2}{10} × \frac{1}{10}

Now we add across

2 + 1 = 3

------------  

10 + 10 = 10 ( When adding fractions like these the denominator stays the same)

So your answer is...

\frac{3}{10}

Good Luck! :)

7 0
3 years ago
A number represented by x times -0.4 is 2.5, what is the value of x?
-BARSIC- [3]
-0.4x=2.5 divide both sides by -0.4

x=-6.25
5 0
3 years ago
Please help me out !!!
asambeis [7]

Answer:

i cant see the exponent sorry

Step-by-step explanation:

5 0
3 years ago
In a survey of adults aged 57 through 85​ years, it was found that 86.6​% of them used at least one prescription medication. Com
OleMash [197]

Answer:

a) 272 used at least one prescription​ medication.

b) The 90% confidence interval estimate of the percentage of adults aged 57 through 85 years who use at least one prescription medication is (85.6%, 87.6%).

Step-by-step explanation:

Question a:

86.6% out of 3149, so:

0.866*3149 = 2727.

272 used at least one prescription​ medication.

Question b:

In a sample with a number n of people surveyed with a probability of a success of \pi, and a confidence level of 1-\alpha, we have the following confidence interval of proportions.

\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}

In which

z is the z-score that has a p-value of 1 - \frac{\alpha}{2}.

For this problem, we have that:

n = 3149, \pi = 0.866

90% confidence level

So \alpha = 0.1, z is the value of Z that has a p-value of 1 - \frac{0.1}{2} = 0.95, so Z = 1.645.  

The lower limit of this interval is:

\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.866 - 1.645\sqrt{\frac{0.866*0.134}{3149}} = 0.856

The upper limit of this interval is:

\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.866 + 1.645\sqrt{\frac{0.866*0.134}{3149}} = 0.876

For the percentage:

0.856*100% = 85.6%

0.876*100% = 87.6%.

The 90% confidence interval estimate of the percentage of adults aged 57 through 85 years who use at least one prescription medication is (85.6%, 87.6%).

7 0
3 years ago
Other questions:
  • What is the answer to the equation 4×-5=3×-1?
    5·1 answer
  • Help me plz it would be greatly appreciated.
    9·2 answers
  • Guys i got an easy question for u...How is 3.098 written in words?(Easy)
    12·2 answers
  • A $20,000 car decreases in value by 15% each year how much is the car worth after three years
    15·2 answers
  • What are the factors in 6x(x+3)?
    15·1 answer
  • A Alex caught 8 fish while his dad caught 24 fish how can the relationship between the number a fish Alex caught and the number
    15·1 answer
  • target sells a camera for $108. During a black friday sale, the canera is on sale for 30% off. What is the sale price of the cam
    14·1 answer
  • Help help help help help
    15·1 answer
  • What is the median for the following set of data?<br><br> 5, 7, 9, 11, 13, 13
    11·1 answer
  • Can an octagon have interior angles that measure 100 degrees, 156 degrees, 125 degrees, 90 degrees, 175 degrees, 160 degrees, an
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!