A bag contains 9 discs of which 4 are red, 3 are blue and 2 are yellow. The discs are similar in shape and size. A disc is drawn at random from the bag. Find the probability that it is either red or blue.

Question

A bag contains 9 discs of which 4 are red, 3 are blue and 2 are yellow. The discs are similar in shape and size. A disc is drawn at random from the bag. Find the probability that it is either red or blue. (A)  (2/9) (B)  (7/9) (C)  (1/9) (D)  (4/9)

Tardigrade Admin · Accepted Answer

There are 9 discs in all so the total number of possible outcomes is 9. Let the events A, B, C be defined as A: 'the disc drawn is red' B: 'the disc drawn is yellow' C: 'the disc drawn is blue' The number of red discs = 4, i.e., n(A) = 4 Hence P(A) = (4/9) The number of blue discs = 3, i.e., n(C) = 3 Therefore, P(C) = (3/9) =(1/3) The event 'either red or blue' may be described by the set 'A or C' Since, A and C are mutually exclusive events, we have P(A or C) = P(A ∪ C) = P(A) + P(C) =(4/9) + (1/3) = (7/9)

Q. A bag contains $9$ discs of which $4$ are red, $3$ are blue and $2$ are yellow. The discs are similar in shape and size. A disc is drawn at random from the bag. Find the probability that it is either red or blue.

$\frac{2}{9}$

$\frac{7}{9}$

$\frac{1}{9}$

$\frac{4}{9}$

Q. A bag contains 9 discs of which 4 are red, 3 are blue and 2 are yellow. The discs are similar in shape and size. A disc is drawn at random from the bag. Find the probability that it is either red or blue.

92​

97​

91​

94​

Q. A bag contains $9$ discs of which $4$ are red, $3$ are blue and $2$ are yellow. The discs are similar in shape and size. A disc is drawn at random from the bag. Find the probability that it is either red or blue.

$\frac{2}{9}$

$\frac{7}{9}$

$\frac{1}{9}$

$\frac{4}{9}$