Question

From 25 identical cards, numbered 1, 2, 3, 4, 5, ……, 24, 25: one card is drawn at random. Find the probability that the number on the card drawn is a multiple of 5.

Answer 1

There are 25 cards from which one card is drawn. 

Total number of elementary events = n(S) = 25 

From number 1 to 25, there are 5 number which are multiple of 5 i.e. {5, 10, 15, 20, 25}

Favorable number of events = n(E) = 5 

Probability of selecting cards with a multiple of 5 = `(n(E))/(n(S)) = 5/25 = 1/5`