Total possible ways of visiting shop by them = 5 x 5 = 25
(i) They can visit the shop on a 11 week days Tuesday to Saturday.
Let A be the favourable outcomes of visiting shop by them on the same day = 5 Then, n(A) = 5
(ii) Let Be be the favourable outcomes of visiting shop on the different days by them = 25 – 5 = 20 days.
i.e. n(B) = 20
Therefore, P(B) =
(iii) Shyam T W Th. F
Ekta W Th. F S
Ekta T W Th. F
Shyam W Th. F S
Let A be the favourable outcomes of visiting shop on consecutive days.
Then, n(A) = 8
Therefore, P(A) = .
A box contains 12 balls out of which x are black. If one ball is drawn at random from the box, what is the probability that it will be a black ball? If 6 more black balls are put in the box, the probability of drawing a black ball is now double of what it was before. Find x.