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
victus00 [196]
3 years ago
14

Few students manage to complete their schooling without taking a standardized admissions test such as the Scholastic Achievement

Test, or SAT (used for admission to college); the Law School Admissions Test, or LSAT; and the Graduate Record Exam, or GRE (used for admission to graduate school). Sometimes, these multiple-choice tests discourage guessing by subtracting points for wrong answers. In particular, a correct answer will be worth +1 point, and an incorrect answer on a question with five listed answers (a through e) will be worth −1/4 points.
What is the expected value of eliminating one answer and guessing among the remaining four possible answers?
What is the expected value of eliminating three answers and guessing between the remaining two possible answers?
Mathematics
1 answer:
slega [8]3 years ago
6 0

Answer:

Step-by-step explanation:

Assuming there is a punitive removal of one point for an incorrect response.

Five undiscernable choices: 20% chance of guessing correctly -- Expectation: 0.20*(1) + 0.80*(-1) = -0.60

Four undiscernable choices: 25% chance of guessing correctly -- Expectation: 0.25*(1) + 0.75*(-1) = -0.50

I'll use 0.33 as an approzimation for 1/3

Three undiscernable choices: 33% chance of guessing correctly -- Expectation: 0.33*(1) + 0.67*(-1) = -0.33 <== The approximation is a little ugly.

Two undiscernable choices: 50% chance of guessing correctly -- Expectation: 0.50*(1) + 0.50*(-1) = 0.00

And thus we see that only if you can remove three is guessing neutral. There is no time when guessing is advantageous.

One Correct Answer: 100% chance of guessing correctly -- Expectation: 1.00*(1) + 0.00*(-1) = 1.00

You might be interested in
Find the missing values assuming continuously compounded interest. (Round your answers to two decimal places.)
alexdok [17]

Answer:

<h2>$3448.81</h2>

Step-by-step explanation:

Using the compound interest formula to calculate the amount compounded after 10years.

A = P(1+r)^{nt}

P = principal  = $2000

r = rate (in %) = 5.6%

t = time (in years) = 10years

n = 1year = time used in compounding

A = 2000(1+0.056)^{10} \\A = 2000(1.056)^{10}\\A = 2000*1.7244046\\A = 3448.81 (to\  2dp)

Amount compounded after 10 years is $3448.81

4 0
3 years ago
The diameter of the moon is about 3500 km. Approximate the surface area of the moon using the formula for the surface area of a
horrorfan [7]

Answer:

3.8465 *10^7 square kilometers

Step-by-step explanation:

The surface area of a sphere can be found using the formula SA=4\pi r^2. Since the diameter is 3500 km then its radius is half of this. 3500 divided in two is 1,750 units. Substitute r=1,750.

SA=4\pi r^2\\SA = 4 \pi (1750)^2\\SA = 4 \pi *3,062,500\\SA =38,465,000

The surface area of the moon is about 38,465,000 square kilometers. Write this is scientific notation using base. 3.8465 *10^7

5 0
3 years ago
The winner of the local triathlon swam 0.5 miles, biked 15 miles and ran 2.5 miles. He finished the race in 54 minutes. For the
AnnZ [28]

Based on the information given, the speed is 20 miles per hour.

From the information given, the winner of the local triathlon swam 0.5 miles, biked 15 miles and ran 2.5 miles and he finished the race in 54 minutes.

Note that 54 minutes = 0.9 hour.

The speed will be:

= (0.5 + 15 + 2.5) / 0.9

= 18/0.9

= 20 miles per hour.

Learn more about speed on:

brainly.com/question/4931057

3 0
2 years ago
Read 2 more answers
A balanced dime is tossed three times. The possible outcomes are represented in the table.
elena-s [515]

the last two ones be the same, the outcomes would be TTT,HTT,THH,HHH

so the probability is 4/8 = 1/2.

5 0
3 years ago
Which expression is equivalent to 24 ⋅ 2−7? 1 over 2 to the power of 11 1 over 2 to the power of 3 23 211
lawyer [7]
I over 2 to the power 11
5 0
3 years ago
Read 2 more answers
Other questions:
  • HELP I NEED AN ANSWER ASAP!!
    15·2 answers
  • CAN SOMEONE HELP ME WITH REFLECTIONS...ILL GIVE BRAINLEST AND POINTS​
    14·1 answer
  • What is 1 plus 2 plus 3.... plus 200?
    5·2 answers
  • A premature infant weighing 3lbs is ordered to 1 milligram per gram of a drug. How many milligrams should you administer to the
    6·1 answer
  • in a bag there are 6green balls4 blue balls and 5 yellow balls what is the probability of choosing a green ball ​
    11·2 answers
  • Find the values of the variables <br> i will give brainliest to anyone who’s right.
    14·1 answer
  • (2.4 x 10^2) (6.1 x 10^5
    10·2 answers
  • What number must be added to -9 to equal +4?
    8·1 answer
  • The Lakeside Legends, a broomball team, joined a 20-team league. They played each of their 19 opponents 3 times. Every broomball
    5·1 answer
  • a team of 15 workers cad do a job in 7 hours. How long would this work take if the team has 35 people?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!