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49 votes
49 votes

A deck of $5$ cards (each carrying a distinct number from $1$ to $5$) is shuffled thoroughly. Two cards are then removed one at a time from the deck. What is the probability that the two cards are selected with the number on the first card being one higher than the number on the second card?
 

  1. $\left(\dfrac{1}{5}\right)$  
  2. $\left(\dfrac{4}{25}\right)$  
  3. $\left(\dfrac{1}{4}\right)$  
  4. $\left(\dfrac{2}{5}\right)$
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7 Answers

2 votes
2 votes
The possible events are
(2,1) (3,2) (4,3) (5,4).
So only 4 possibilities are there and sample space will be,
5C1 × 4C1 = 20
So probability = 4/20 = 1/5

Answer:A
1 votes
1 votes

Number of ways cards can be arranged = 5!

Favorable ways =

5 4 _ _ _ => 6 ways

4 3 _ _ _ => 6 ways

3 2 _ _ _ => 6 ways

2 1 _ _ _ => 6 ways

(6+6+6+6)/5! => 1/5 => A

Answer:

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