All categories

3 years ago

Anna scored 27 questions right on her test. She scored a 90%. How many questions were on the test?

Mathematics

2 answers:

-BARSIC- [3]3 years ago

7 0

Answer:

Step-by-step explanation:

divide 27 by 9

you get 3

add 3 to 27 because 3 = 10%

30 questions

hope this helped! :)

valkas [14]3 years ago

6 0

Answer: 30

Step-by-step explanation: 30 times .9 is 27, meaning that 90%of her grade would be 27.

You might be interested in

In a survey of randomly selected 3,900 family-owned businesses with revenues exceeding $1 million a year, it was found that 1,91

Maurinko [17]

Answer:

a) The 90% confidence interval to estimate the proportion of family-owned businesses without strategic business plans is (0.4768, 0.5032). This means that we are 90% sure that the true proportion of all family-owned businesses without strategic business plans is between these two values.

b) Wider

Step-by-step explanation:

Question a:

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 $1 - \frac{\alpha}{2}$ .

In a survey of randomly selected 3,900 family-owned businesses with revenues exceeding $1 million a year, it was found that 1,911 of them had no strategic business plan.

This means that $n = 3900, \pi = \frac{1911}{3900} = 0.49$

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:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.49 - 1.645\sqrt{\frac{0.49*0.51}{3900}} = 0.4768$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.49 + 1.645\sqrt{\frac{0.49*0.51}{3900}} = 0.5032$

The 90% confidence interval to estimate the proportion of family-owned businesses without strategic business plans is (0.4768, 0.5032). This means that we are 90% sure that the true proportion of all family-owned businesses without strategic business plans is between these two values.

Question b:

The margin of error is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

The higher the confidence level, the higher the value of z, thus the higher the margin of error and the interval is wider. Thus, a 99% confidence interval is wider than a 90% confidence interval.

3 0

2 years ago

What is the quadratic regression equation for the data set?

Svet_ta [14]

Answer:

y=−0.004x2+0.415x−0.546

6 0

3 years ago

What is the median of the ages in this stem-and-leaf plot? 43 45 46 47

ICE Princess25 [194]

To find a median of an even amount of numbers, add the two middle numbers, and divide by two.

45 + 46 = 91

91/2 = 45.5

45.5 is your median

hope this helps

6 0

3 years ago

Read 2 more answers

What is the product of (5-2i)(3+i)

zvonat [6]

The is the answer on my paper:

3 0

2 years ago

A cone is placed inside a cylinder, as shown below. They have the same height and diameter. About how much space is inside the c

nadezda [96]

The space is inside the cylinder but outside the cone is 200π cubic FT or 628.32 cubic FT.

It is defined as the three-dimensional shape in which the base is a circular shape and if we go from circular base to top the diameter of the circle reduces and at the vertex, it becomes almost zero.

We know the volume of the cylinder is given:

$\rm V = \pi r^2 h$