6. In a lottery, three numbers are chosen from 0 to 9. You win if the three numbers you pick match the three numbers selected by the lottery machine.
a. What is the probability of winning this lottery if the numbers cannot be repeated?
b. What is the probability of winning this lottery if the numbers can be repeated?
c. What is the probability of winning this lottery if you must match the exact order that the lottery machine picked the numbers?

Respuesta :

Answer:

a)  1/120

b) 1/ 1000

c) 1/720

Step-by-step explanation

a) We have 10 numbers and combinations of 10 elements taking in group of three is:

V₁₀,₃  =  10! /3! ( 10 - 3 ) !   V₁₀,₃  =  10*9*8/6  V₁₀,₃  = 720/6

V₁₀,₃  = 120

So total number of outcomes is 120 therefore the probability of winning is 1 /120

b) Now if numbers can be repeated

each time we pick up one number its probability is 1/10 then for winning the lottery we will have to get:

1/10*1/10+1/10  = 1 / 1000

c) If additionaly to case a) above we need to match the order then

C₁₀,₃  =  10! / ( 10- 3 ) !     ⇒  C₁₀,₃  =  10*9*8  ⇒   C₁₀,₃  = 720

C₁₀,₃  =  720 then the probability of winning is

1/720

By finding the numbers of combinations, we will see that:

  • a) P = 1/120
  • b) P = 6/1000
  • c) P = 1/1000

How to get the probabilities?

The probability will be given by 1 over the total number of possible combinations.

a) If the numbers cannot be repeated, then the total number of combinations is given by:

  • For the first number, there are 10 options.
  • For the second number, there are 9 options.
  • For the third number, there are 8 options.

The number of combinations is given by the product between the numbers of options:

c = 10*9*8 = 720

Then the probability of winning in this case is:

P = 1/720

But the order of the numbers does not matter, so we multiply by the permutations of the 3 numbers = 3! = 3*2 = 6

P = 6/720 = 1/120

b) If the numbers can be repeated, then we have 10 options for the 3 numbers, and the number of combinations is given by:

C = 10*10*10 = 1000

Then the probability is:

P =1/1000

Again, here the order does not matter, so we have:

P = 6/1000

c) Now the order does matter, so this time the probability is just:

P = 1/1000.

If you want to learn more about probabilities, you can read:

https://brainly.com/question/251701