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
lorasvet [3.4K]
3 years ago
6

A student takes a true-false test that has 12 questions and guesses randomly at each answer. Let X be the number of questions an

swered correctly. Find P(10 or more)
Mathematics
1 answer:
snow_lady [41]3 years ago
7 0

Step-by-step answer:

assuming the true-false test have equal probabilities (each 0.5), we can use the binomial probability to calculate the sum of probabilities of getting 10, 11 or 12 questions correctly out of 12.

p=probability of success = 0.5

N=number of questions

x = number of correct answers

then

P(x) = C(N,x)(p^x)((1-p)^(N-x))

where C(N,x) = N!/(x!(N-x)!) = number of combinations of taking x objects out of N.

P(10) = C(12,10)(0.5^10)((1-0.5)^2) = 33/2048 = 0.01611

P(11) = C(12,11)(0.5^11)((1-0.5)^1)     =  3/1024 = 0.00293

P(12) = C(12,12)(0.5^12)((1-0.5)^0) =  1/4096 = 0.00024

for a total probability of 79/4096 = 0.01929

You might be interested in
A what is a letter or symbol that represents some unknown value
aleksley [76]
Unknown values can be taken as anything , for example : the most common is x for unknown values and sometimes, for angles we can take θ(theta).

it is totally upto you!
8 0
3 years ago
Read 2 more answers
What is 3x-8-8x=42 answer nowwwwwwwwwwwwwwwwwwwwwwwwwww
eimsori [14]

The answer is x = -10

Explanation:

3x-8-8x=42

3x-8x = 42-8

-5x = 50 ---> do

x = -10

4 0
2 years ago
Find the value of x below
ehidna [41]

Answer:

x=58 degrees

Step-by-step explanation:

The angle DB is equal to 90 degrees, so if you subtract 32 from 90 you get x, which is 58.

3 0
3 years ago
Raquel takes her pulse in order to determine her resting heart rate, measured in beats per minute (\text{bpm})(bpm)left parenthe
murzikaleks [220]

Answer:

Raquel's heart rate is slower.

4 0
3 years ago
The annual Gross Domestic Product (GDP) of a country is the value of all of the goods and services produced in the country durin
Vladimir [108]
F=5.77X10^9(1.032^(y-1985)), we want to know when this is:

2.2X10^12=5.77X10^9(1.032^(y-1985))

381.2825=1.032^(y-1985)

ln(3,812825)=(y-1985)ln(1.032)

ln(3.812825)/ln(1.032)=y-1985

y=1985+ln(3.812825)/ln(1.032)

y≈2027.5  

So GDP will reach 2.2 trillion during the year 2027.
5 0
3 years ago
Other questions:
  • Rewrite the equation so that it does not have fractions. 3/4x-4=5/6 Also can you reply asap and help me with other problems?
    14·1 answer
  • An arrangement of bowling
    15·1 answer
  • Give two real-world situations that could be represented by the value 30
    8·1 answer
  • During a scuba dive, Lainey descended to a point 20 feet below the ocean surface.She countined her descent at a rate of 20 feet
    12·1 answer
  • Ms.Discher is 5.5 feet tall and Her shadow is 4 feet long.How tall is the tree in her yard?
    14·1 answer
  • When comparing linear and exponential functions, which of the following is true?
    13·1 answer
  • 5x-11=24<br> ????????????
    10·2 answers
  • 20a + 158 + 6c = 20 (6) +15(4) + 6(8)<br> ?<br> ?<br> +<br> ?<br> 2<br> +<br> ?
    7·1 answer
  • Find an angle with a positive measure and an angle with a negative measure that is coterminal with each angle 210° and - 120°
    7·1 answer
  • Please help! -The volume inside a rectangular storage room is 2,052 cubic feet. The room is 9 feet high. Find the area of the fl
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!