Question

a box contains 19 balls bearing numbers 1, 2, 3,..., 19 respectively. A
is drawn at random from the box. Find the probability that the
number on the ball is
(i) a prime number
(ii) divisible by 3 or 5
(iii) neither divisible by 5 nor by 10 (iv) an even number.​

Answer 1

Answer:

(i) 8/19 (ii) 8/19 (iii) 11/19 (iv) 9/19

Step-by-step explanation:

(i) Favourable outcomes = 2,3,5,7,11,13,17 and 19.

So, P(Prime Number) is 8/19

(ii) Favourable outcomes =

3,5,6,9,10,12,15 and 18.

So, P(Number divisible by 3 or 5) is 8/19

(iii) Favourable outcomes =

1,2,4,7,8,11,13,14,16,17 and 19.

So, P(Number neither divisible by 3 nor 5) is 11/19

(iv) Favourable outcomes =

2,4,6,8,10,12,14,16 and 18.

So, P(Even Number) is 9/19

Answer 2

Answer

(i) 8/19 (ii) 8/19 (iii) 11/19 (iv) 9/19

Step-by-step explanation:

(i) Favourable outcomes = 2,3,5,7,11,13,17 %3D and 19. So, P(Prime Number) is 8/19

(ii) Favourable outcomes = 3,5,6,9,10,125 and 18. So, P(Number divisible by 3 or 5 is 8/19

is 8/19 3

(iii) Favourable outcomes = 1,2,4,7,8,11,13,14,16,17 and 19. So, P(Number neither divisible by 3 nor 5) is 11/19

(iv) Favourable outcomes = 2,4,6,8,10,12,14,16 and 18. So, P(Even Number) is 9/19