Question

Cards numbered 1 to 30 are put in a bag. A card is drawn at random from this bag. Find the probability that the number on the drawn card is not divisible by 3

 

Answer 1

Total number of outcomes = 30
 There are 10 numbers divisible by 3.
∴ Number of numbers not divisible by 3 = 30 − 10 = 20
So, the favourable number of outcomes are 20.
∴ P(drawing a card with number not divisible by 3) =\[\frac{\text{ Favourable number of outcomes }}{\text{ Total number of outcomes }} = \frac{20}{30} = \frac{2}{3}\]