Question

A box contains 20 cards numbered from 1 to 20 a card is drawn at random from the box find the probability that the number on the drawn card is (2015D) i)divisible by 2 or 3 ii)a prime number

Answer 1

Answer:

a prime number because their probality will be 1/20

Answer 2

Answer:

Let E be event of drawing a card with number divisible by 2 or 3 from the cards with numbers 1 to 20

Numbers divisible by 2 or 3 from 1 to 20=2,3,4,6,8,9,10,12,14,15,16,18,20

No. of favorable outcomes=13

Total no. of possible outcomes =20

We know that, Probability P(E) =

(Total no.of possible outcomes)

(No.of favorable outcomes)

=

20

13

Therefore, the probability that a number on the card selected from numbers 1 to 20 divisible by 2 and 3 is

20

13