Question

You roll a die. What is the probability that you’ll get a number less than 3?0.3330.50.6670.75

Answer 1

Recall that the numbers in a die are 1,2,3,4,5,6.

`S=\mleft\lbrace1,2,3,4,5,6\mright\rbrace`

Hence the number of possible outcomes is 6.

`n(S)=6`

We need a number less than 3. Let A be this event.

`A=\mleft\lbrace1,2\mright\rbrace`

The favorable outcome is 2.

`n(A)=\mleft\lbrace1,2\mright\rbrace`

Since there are 1,2 less than 3 in a die.

`P(A)=\frac{Favourable\text{ outcomes}}{\text{Total outcomes}}=(n(A))/(n(S))`

Substitute n(A)=2 and n(S)=6, we get

`P(A)=(2)/(6)=(1)/(3)=0.333`

Hence the required probability is 0.333.