A box contains 10 white, 6 red and 10 black balls. A ball is drawn at random from the ox. What is the probability that the ball drawn is either white or red?

As box contains 26 balls. Let S represents the sample space.


n(S) = 26


Let W denotes the event of drawing a white ball and R represents event of drawing red ball.


As, n(W) = 10 and n(R) = 6


P(W) = 10/26 = 5/13


And P(R) = 6/26 = 3/13


As both events have nothing in common so we can say that they are mutually exclusive.


We need to find the probability of the event such that ball drawn is red or white.


P(Red or White) = P(R W)


As events are mutually exclusive


P(R W) = P(R) + P(W)


P(R W) = 3/13 + 5/13 = 8/13


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