Question

If one card is randomly selected from a well-shuffled standard deck of 52 cards, what is the probability that the card selected is not a spade

Answer 1

Explanation:

Given

Total Number of Cards = 52

Required

Probability of not picking a spade

Let P(S) represents the probability of picking a spade;

`P(S) = (n(S))/(Total)`

Where n(S) is the number of spades

`n(S) = 13`

Substitute
`n(S) = 13` and 52 for Total

`P(S) = (13)/(52)`

`P(S) = (1)/(4)`

Let P(S') represents the probability of not picking a spade

In probability;

`P(S) + P(S') = 1`

Substitute
`P(S) = (1)/(4)`

`(1)/(4) + P(S') = 1`

`P(S') = 1 - (1)/(4)`

`P(S') = (4-1)/(4)`

`P(S') = (3)/(4)`

`P(S') = 0.75`

Hence, the probability of not selecting a spade is 3/4 or 0.75