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Probability, SM-Bank 021 MC

There are 20 raffle tickets, numbered 1 to 20, in a box.

Three prizes are given away by choosing three tickets from the box. Each ticket can win only one prize.

The first ticket drawn is number 15 and it wins the third prize.

Which of the following is not possible?
 

  1. Second prize is won by number 2.
  2. First prize is won by a prime number.
  3. Second prize is an even number.
  4. First prize is won by number 15.
Show Answers Only

\(D\)

Show Worked Solution

\(\text{“First prize is won by number 15” is impossible because}\)

\(\text{number 15 has already been chosen and won 3rd prize.}\)

\(\text{(Note that there is no replacement of tickets.)}\)

 
\(\Rightarrow D\)