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
GuDViN [60]
3 years ago
12

You are to take a multiple-choice exam consisting of 100 questions with 2 possible responses to each question. Let x represent t

he number of correct responses on the test. A) What is your expected score on the exam?B) Compute the variance and standard deviation of x.
Mathematics
1 answer:
Elena-2011 [213]3 years ago
3 0

Answer:

50 ;

25 ;

5

Step-by-step explanation:

Given that:

Number of multiple choice questions = 100

Number of possible responses = 2

Hence, probability of success, p = 1/2 = 0.5

Using normal approximation :

The expected score = mean = n*p

Expected score (X) = 100 * 0.5 = 50

standard deviation = std(X) = √

Var(X) = n*p*q

q = 1 - p = 1 - 0.5 = 0.5

Variance = Var(X) = (100 * 0.5 * 0.5)

Var(X) = 25

Var(X) = 25

The Standard deviation (Std) = √Var(X)

Std(X) = √25

Std(X) = 5

You might be interested in
Eleven members of the Middle School Math Club each paid the same amount for a guest speaker to talk about problem solving at the
tiny-mole [99]
The missing digit is number 3. The total amount should be $132

I multiplied 11 by the numbers 10 and above to get the possible three digit answer who has 1 as the first digit and 2 as the last digit.

11 x 10 = 110
11 x 11 = 121
11 x 12 = 132

The 11 members of the Middle School Math club each paid $12 for a guest speaker.
7 0
2 years ago
Find an equivalent fractions for each given fraction 60/12
evablogger [386]

Very easy to do this.

60/12 is your fraction.

Multiply numerator and denominator by the same number.

60*2/12*2 = 120/24

120/24 = 5

You can also simplify.

60/12 = 5

12/12 = 1

5/1 = 5

60/12 = 5

8 0
3 years ago
Read 2 more answers
How to solve бу - 5 = 7
WARRIOR [948]

Answer:

y = 2

Step-by-step explanation:

6y-5=7

   +5  +5

6y=12

/6   /6

y=2

6 0
2 years ago
HELP ASAP NEEED THE CORRECT ANSWER
Tatiana [17]

The right answer is Option A.

Step-by-step explanation:

Given,

Amount in Jason's account = $300

Bills paid = \frac{1}{4}

Remaining balance after bills = -$50

Let,

x be the amount of bills.

Amount in account - Bills paid*Amount of bills = Remaining balance

300-\frac{1}{4}x=-50\\-\frac{1}{4}x+300=-50

The equation -\frac{1}{4}x+300=-50 can be used to find x.

The right answer is Option A.

Keywords: equation, subtraction

Learn more about subtraction at:

  • brainly.com/question/10710410
  • brainly.com/question/10717746

#LearnwithBrainly

5 0
3 years ago
A grocer sells 30 loaves of bread a day. The cost is $2.50 per loaf. The grocer estimates that for each $0.50 increase in cost,
Viktor [21]

Answer:

none of the above

Step-by-step explanation:

The grocer's revenue will be the product of the number of loaves sold (30-2x) and their price (2.50+0.50x).

Revenue will be positive for values of x between those that make these factors be zero. The number of loaves sold will be zero when ...

... 30 -2x = 0

... 15 -x = 0 . . . . . divide by 2

... x = 15 . . . . . . . add x

The price of each loaf will be zero when ...

... 2.50 +0.50x = 0

... 5 + x = 0 . . . . . . . multiply by 2

... x = -5 . . . . . . . . . . subtract 5

Revenue will be positive for any number of increases greater than -5 and less than 15.

_____

D is the best of the offered choices, but it is incorrect in detail. -5 is a number less than 15, but will give zero revenue.

4 0
3 years ago
Other questions:
  • the probability that people buy candy movies at 45% if they're 160 people in the theater about how many bought candy​
    8·1 answer
  • Quick question what’s 2ab+3b+7b+3a•3a•b+4b-8ab•8ab+5a•5a•b-12ab?
    5·1 answer
  • 2.34 x 10^65   + 9.2 x10^66  
    8·1 answer
  • Answer of 18x2+3x-15 with solution
    8·1 answer
  • Write the place value as the denominator and write 7 as the numerator.
    9·1 answer
  • ????????????????????
    6·2 answers
  • Full working out for this question please.
    6·2 answers
  • What is £8.19 minus 10%
    8·2 answers
  • Fr ee poi nts. dele ting my acco unt so here you go​
    11·2 answers
  • What is limit of startfraction x cubed minus 1 over x minus 1 endfraction as x approaches 1?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!