Question

21 cards are numbered 1, 2, ...., 20, 21 and placed in a box. The cards are mixed thoroughly. A card is drawn at random from the box. Find the probability that the number on the card is (i) an even number (ii) a prime number (iii) divisible by four

Answer 1

Answer:

(i)10/21

(ii)8/21

(iii)5/21

Step-by-step explanation:

(i) Even no.=2,4,6,8,10,12,14,16,18,20

=10/21

(ii) Prime no.=2,3,5,7,11,13,17,19

=8/21

(iii) Multiple 0f 4=4,8,12,16,10

=5/21