A textbook has a regular selling price of $79.99, and is on sale for $65.50. What is the markdown rate?

Determine the mean of the data. Round to the nearest tenth. 6, 9, 15, 22, 30, 36

pshichka [43]

To find the mean you add all the numbers and divide it by the amount of numbers there is so add
6+9+15+22+30+36=118
there is 6 number so divide 118 by 6
118/6=19.6666666667 rounded to the nearest tenth it would be 20
So your mean would be 20
let me know if you have any questions

3 0

3 years ago

How many different primes are in the prime factorization of 65529009

Tems11 [23]

Answer:

6 different primes.

3, 7, 13, 29, 31 , 89.

Step-by-step explanation:

Try dividing by primes starting with 3:

3 ) 65529009

3 ) 21843003

7) 7281001

13) 1040143

29) 80011

31 ( 2759

89. 89 is a prime number.

7 0

3 years ago

A college requires applicants to have an ACT score in the top 12% of all test scores. The ACT scores are normally distributed, w

DochEvi [55]

Answer:

a) The lowest test score that a student could get and still meet the colleges requirement is 27.0225.

b) 156 would be expected to have a test score that would meet the colleges requirement

c) The lowest score that would meet the colleges requirement would be decreased to 26.388.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 21.5, \sigma = 4.7$

a. Find the lowest test score that a student could get and still meet the colleges requirement.

This is the value of X when Z has a pvalue of 1 - 0.12 = 0.88. So it is X when Z = 1.175.

$Z = \frac{X - \mu}{\sigma}$

$1.175 = \frac{X - 21.5}{4.7}$

$X - 21.5 = 1.175*4.7$

$X = 27.0225$

The lowest test score that a student could get and still meet the colleges requirement is 27.0225.

b. If 1300 students are randomly selected, how many would be expected to have a test score that would meet the colleges requirement?

Top 12%, so 12% of them.

0.12*1300 = 156

156 would be expected to have a test score that would meet the colleges requirement

c. How does the answer to part (a) change if the college decided to accept the top 15% of all test scores?

It would decrease to the value of X when Z has a pvalue of 1-0.15 = 0.85. So X when Z = 1.04.

$Z = \frac{X - \mu}{\sigma}$

$1.04 = \frac{X - 21.5}{4.7}$

$X - 21.5 = 1.04*4.7$

$X = 26.388$

The lowest score that would meet the colleges requirement would be decreased to 26.388.

6 0

3 years ago

Let alpha and beta be conjugate complex numbers such that frac{\alpha}{\beta^2} is a real number and alpha - \beta| = 2 \sqrt{3}

miskamm [114]

Answer:

$-3+i\sqrt{3} , 1+\sqrt{3}$

Step-by-step explanation:

Given that alpha and beta be conjugate complex numbers

such that frac{\alpha}{\beta^2} is a real number and alpha - \beta| = 2 \sqrt{3}.

Let

$\alpha = x+iy\\\beta = x-iy$

since they are conjugates

$\alpha-\beta = x+iy-(x-iy)\\= 2iy= 2i\sqrt{3} \\y =\sqrt{3}$

$\frac{\alpha}{\beta^2} }\\=\frac{x+i\sqrt{3} }{(x-i\sqrt{3})^2} \\=\frac{x+i\sqrt{3}}{x^2-3-2i\sqrt{3}} \\=\frac{x+i\sqrt{3}((x^2-3+2i\sqrt{3}) }{(x^2-3-2i\sqrt{3)}(x^2-3-2i\sqrt{3})}$

Imaginary part of the above =0

i.e. $\sqrt{3} (x^2-3)+2x\sqrt{3} =0\\x^2+2x-3=0\\(x+3)(x-1) =0\\x=-3,1$

So the value of alpha = $-3+i\sqrt{3} , 1+\sqrt{3}$

3 0

3 years ago

The sides of two cubes are in the ratio 2:1. What is the ratio of their volumes ?

olasank [31]

Please mark as brainliest

Answer:

we know that, Volume of cube=a³

Let volume of 1st cube be 2x with side a and other be x with side A (according to given ratio)

Step-by-step explanation:

ATQ: 2x=a³ and, x=A³

a=³√2x and, A=x

we know that, surface area of cube is 6a²

Thus, surface area of 1st cube = 6(³√2x)²

= 6³√4x²

Surface area of 2nd cube=6(x)²=6x²

Ratio of S.A=(6³√4x²)÷(6x²)

Ratio of S.A=³√4:1

Please mark as brainliest

Have a great day, be safe and healthy

Thank u

XD

5 0

3 years ago