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2 years ago

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Standard tests, such as the SAT or ACT or MCAT, tend to make extensive use of multiple-choice questions because they are easy to

grade using software. If one such multiple choice question has possible correct answers of a, b, c, d, e, what is the probability of a wrong answer if the answer is a random guess

1 answer:

svet-max [94.6K]2 years ago

8 0

Answer:

4/5

Step-by-step explanation:

Given that:

Number of options = a, b, c, d, e

Number of correct answer choice = 1

Therefore, number of wrong answers = 4

Recall :

Probability = (number required outcome / number of total possible outcomes)

P(wrong answer) :

Number of Required outcome = number of wrong answer choices = 4

Total answers = 5

Hence,

P(wrong answer) = 4 / 5 = 0.8

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PLZ Hurry!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!The sum of two numbers is 19 and their difference is 7, What are the two num

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Answer:

13 and 6

Step-by-step explanation:

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2 years ago

2. In how many ways can 3 different novels, 2 different mathematics books and 5 different chemistry books be arranged on a books

insens350 [35]

The number of ways of the books can be arranged are illustrations of permutations.

When the books are arranged in any order, the number of arrangements is 3628800
When the mathematics book must not be together, the number of arrangements is 2903040
When the novels must be together, and the chemistry books must be together, the number of arrangements is 17280
When the mathematics books must be together, and the novels must not be together, the number of arrangements is 302400

The given parameters are:

$\mathbf{Novels = 3}$

$\mathbf{Mathematics = 2}$

$\mathbf{Chemistry = 5}$

<u />

<u>(a) The books in any order</u>

First, we calculate the total number of books

$\mathbf{n = Novels + Mathematics + Chemistry}$

$\mathbf{n = 3 + 2 + 5}$

$\mathbf{n = 10}$

The number of arrangement is n!:

So, we have:

$\mathbf{n! = 10!}$

$\mathbf{n! = 3628800}$

<u>(b) The mathematics book, not together</u>

There are 2 mathematics books.

If the mathematics books, must be together

The number of arrangements is:

$\mathbf{Maths\ together = 2 \times 9!}$

Using the complement rule, we have:

$\mathbf{Maths\ not\ together = Total - Maths\ together}$

This gives

$\mathbf{Maths\ not\ together = 3628800 - 2 \times 9!}$

$\mathbf{Maths\ not\ together = 2903040}$

<u>(c) The novels must be together and the chemistry books, together</u>

We have:

$\mathbf{Novels = 3}$

$\mathbf{Chemistry = 5}$

First, arrange the novels in:

$\mathbf{Novels = 3!\ ways}$

Next, arrange the chemistry books in:

$\mathbf{Chemistry = 5!\ ways}$

Now, the 5 chemistry books will be taken as 1; the novels will also be taken as 1.

Literally, the number of books now is:

$\mathbf{n =Mathematics + 1 + 1}$

$\mathbf{n =2 + 1 + 1}$

$\mathbf{n =4}$

So, the number of arrangements is:

$\mathbf{Arrangements = n! \times 3! \times 5!}$

$\mathbf{Arrangements = 4! \times 3! \times 5!}$

$\mathbf{Arrangements = 17280}$

<u>(d) The mathematics must be together and the chemistry books, not together</u>

We have:

$\mathbf{Mathematics = 2}$

$\mathbf{Novels = 3}$

$\mathbf{Chemistry = 5}$

First, arrange the mathematics in:

$\mathbf{Mathematics = 2!}$

Literally, the number of chemistry and mathematics now is:

$\mathbf{n =Chemistry + 1}$

$\mathbf{n =5 + 1}$

$\mathbf{n =6}$

So, the number of arrangements of these books is:

$\mathbf{Arrangements = n! \times 2!}$

$\mathbf{Arrangements = 6! \times 2!}$

Now, there are 7 spaces between the chemistry and mathematics books.

For the 3 novels not to be together, the number of arrangement is:

$\mathbf{Arrangements = ^7P_3}$

So, the total arrangement is:

$\mathbf{Total = 6! \times 2!\times ^7P_3}$

$\mathbf{Total = 6! \times 2!\times 210}$

$\mathbf{Total = 302400}$

Read more about permutations at:

brainly.com/question/1216161

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2 years ago

List the angles of the triangle below in order from smallest to largest.

Elan Coil [88]

Answer:

M,L,K

Step-by-step explanation:

The angle opposite the side is in the order of their size. So the larger the side the larger the angle

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3 years ago

Jenna works in an ice cream shop. When she starts her shift the tub of chocolate ice cream is 23 full. When she finishes her shi

ipn [44]

Answer:

<em /> $Rate = 1.1/hr$ <em />

<em />

Step-by-step explanation:

Given

$Start = 23$

$End = 16$

$Hours = 6\frac{1}{2}h$

Required

Determine the hourly rate

First, we need to determine the ice cream sold

$Ice\ Cream = 23 - 16$

$Ice\ Cream = 7$

Next, we calculate the hourly rate:

$Rate = Ice\ Cream/Hours$

$Rate = 7/6\frac{1}{2}h$

$Rate = 7/\frac{13}{2}h$

$Rate = 7*\frac{2}{13h}$

$Rate = \frac{14}{13h}$

$Rate = 1.07692307692/hr$

<em /> $Rate = 1.1/hr$ <em> -- Approximated</em>

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2 years ago

Read 2 more answers

Several high schools participated in a study to evaluate the effectiveness of a new computer-based math curriculum. In all these

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Step-by-step explanation:

a

the study is experimental as we do not just observe students performance. 2 techniques were also randomly assigned. there is control over teaching techniques and performance is also observed.

b.

these are the 3 factors: high school, instructions type, scores.

high school has 2 levels. level 1, is 3 high school. level 2: each high school has 4 sections and these 4 have 24 students.

instructions type: 1 level divided into standard and computer based.

scores: 0 ( no level)

c.

high school has between subject combination since there are 3 schools and 4 sections.

instructions type has between too. since there are two different types.

we have 24 students in each section which are within subjects.

d.

score on test is dependent variable

e.

student is basic experimental unit.

4 0

2 years ago