Question 1189691:  Hi, please help me out with this question. It is very confusing and I don't know how to approach it. 
 
The tickets for a raffle have four different numbers chosen from 3- 13, with order not important. Determine the probability of winning first prize, which consists of matching all four numbers? 
 
a. 0.3322%  
b. 0.3% 
c. 29% 
d. 0.3030% 
 Found 2 solutions by  ikleyn, Theo: Answer by ikleyn(52903)      (Show Source): 
You can  put this solution on YOUR website! . 
Hi, please help me out with this question. It is very confusing and I don't know how to approach it. 
The tickets for a raffle have four different numbers chosen from 3- 13, with order not important.  
Determine the probability of winning first prize, which consists of matching all four numbers? 
a. 0.3322% 
b. 0.3% 
c. 29% 
d. 0.3030% 
~~~~~~~~~~~~~~~~~
 
 
There are 11 numbers  3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13.
In all, there are    =   = 330 different combinations of 11 items, taken 4 at a time
(330 quadruples).
Only one such combination (quadruple of numbers) provides winning the first prize.
So, the probability is    = 0.00303 = 0.3030%  (rounded).
ANSWER.  Option (d).
 
 
Solved.
 
 
--------------------
 
 
This problem is on COMBINATIONS.
 
 
On Combinations,  see introductory lessons
 
    - Introduction to Combinations
 
    - PROOF of the formula on the number of Combinations
 
    - Problems on Combinations
 
    - OVERVIEW of lessons on Permutations and Combinations
 
in this site.
 
 
Also,  you have this free of charge online textbook in ALGEBRA-II in this site
 
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.
 
 
The referred lessons are the part of this online textbook under the topic  "Combinatorics: Combinations and permutations". 
 
 
 
Save the link to this textbook together with its description
 
 
Free of charge online textbook in ALGEBRA-II 
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson
 
 
into your archive and use when it is needed.
 
 
 
 
 Answer by Theo(13342)      (Show Source): 
You can  put this solution on YOUR website! there are 11 numbers from 3 to 13. 
you draw 4 times. 
the probability of getting one of the 4 numbers on the first try is 4/11. 
the probability of getting one of the remaining 3 numbers on the second try is 3/10. 
the probability of getting one of the remaining 2 numbers on the third try is 2/9. 
the probability of getting the remaining 1 number on the fourth try is 1/8. 
the combined probabiity is 4/11 * 3/10 * 2/9 * 1/8 = .003030303..... 
that is equal to .30303030.....% 
round that to 4 decimal places to get .3030%. 
that would be selection d.
 
 
 
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