Question

29.
Cards numbered 1 to 30 are put in a bag. A card is drawn at randem from this bag.
Find the probability that the number on the drawn card is.
(a) not divisible by 3.
(b) a prime number greater than 7
(c) not a perfect square number​

Answer 1

Answer:

(a) not divisible by 3 = 2/3

(b) a prime number greater than 7 = 1/5

(c) not a perfect square number = 5/6

Step-by-step explanation:

Total number of cards (n(S)) = 30

(a) 10 cards are divisible by 3 (3,6,9,12,15,18,21,24,27,30)

so n(E) = 30-10 = 20

not divisible by 3 = 20/30 = 2/3

(b) there are 6 prime numbers greater than 7 and less than 30 (11,13,17,19,23,29)

n(E) = 6

probability = 6/30 = 1/5

(c) there are 5 perfect square numbers (1,4,9,16,25)

n(E) = 30-5 = 25

probability = 25/30 = 5/6