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
stira [4]
3 years ago
10

In a clinical study, volunteers are tested for a gene that has been found to increase the risk for a disease. The probability th

at a person carries the gene is 0.1. (a) What is the probability that 4 or more people will have to be tested until 2 of them with the gene are detected? Round your answer to three decimal places (e.g. 0.987). (b) How many people are expected to be tested until 2 of them with the gene are detected?
Mathematics
1 answer:
MrRa [10]3 years ago
4 0

Answer:

a) 0.984

b) 20 people

Step-by-step explanation:

a)

If The probability that a person carries the gene is 0.1, then in a sample of 20 people, 2 should carry the gene.

Now, we want to know how many samples there are with this property.

Since we have 20 elements where 18 are alike (do not carry the gene) and 2 are alike (carry the gene), we have to compute the number of permutations of 20 elements in which 18 are alike and 2 are alike. This number is

\frac{20!}{18!2!}=190

In this 190 20-tuples there are only 3 where the 2 carriers of the gene are in the first 3 places, namely

(1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)

(1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)

(0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)

where 1=carries the gene, 0=does not carry the gene.

So there are 190-3 = 187 elements in which the first 3 elements have no 2 carriers, hence the probability that 4 or more people will have to be tested until 2 of them with the gene are detected is 187/190 = 0.984 (98.4%) rounded to three decimal places.

b)

Given that the probability that a person carries the gene is 0.1, then in a sample of 20 people, 20*0.1 = 2 should carry the gene.

You might be interested in
A tree broke 6 feet from the bottom. If the top landed 12 feet from the base, how tall was the tree before it broke?
spayn [35]

Answer:

7.4 ft

Step-by-step explanation:

7 0
3 years ago
10 pennies are flipped and arranged in a row. How many arrangements of the heads and tails are possible?
DaniilM [7]

Answer:

1000 possible arrangements

Step-by-step explanation:

6 0
3 years ago
Help me out guys :[ aaaaaaaaa
VladimirAG [237]

Answer:

this is explaining how to do it, you need to isolate the variable so you need to substract or add so that she is alone.

Step-by-step explanation:

5 0
2 years ago
When did aiko start jumping?
frosja888 [35]

Answer:

what is aiko?

Step-by-step explanation:

6 0
2 years ago
I will give you brainliest I will give you five stars and I will give you a heart if you can get this correct
BigorU [14]

Answer:

the last one

Hope this helps

-mercury

7 0
3 years ago
Other questions:
  • What order of operations equal -5
    14·1 answer
  • Rosa and Albert receive the same amount of allowance each week . The table shows what part of their allowance they each spent on
    5·1 answer
  • What is the slope of a line that is perpendicular to the line whose equation is 7x−3y=10?
    15·1 answer
  • A farm is to be built in the shape of Quadrilateral ABCD, as shown below.
    15·1 answer
  • LOTS OF POINTS ANSWER ASA P , painter is painting a rectangular wall that measures 25.1 ft by 18.5 ft. Each gallon can of paint
    11·2 answers
  • Please Help!!! I have the answer I just need a step by step explanation. I will give extra points and make you brainiest!!!
    8·1 answer
  • What sine function represents an amplitude of 1, a period of 2π, a horizontal shift of π, and a vertical shift of −4?
    9·1 answer
  • The tent shown has fabric covering all four sides and the floor. What is the minimum amount of fabric needed to construct the te
    8·1 answer
  • I need help figuring out if this is a function or not and why
    13·1 answer
  • 4x^2-y^2 how do you factorize this? with steps pls:)
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!