There are 25 balls in a box, each of which could be red, blue or white in color. Each ball also has a number from 1 to 10 on it.
Let’s understand this in more detail by taking a few examples.
Can we have a red ball with a 7 on it? Yes we can. Can 7 be on a green ball as well? That’s possible as well.
Now that the situation is clearer, let’s proceed to understand the question stem. We need to find the probability that the one ball picked at random from the box is white or has an even number painted on it.
Using Venn diagrams is a great way to solve this question from this stage onwards.
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From the Venn diagram, it’s clear that to find the required probability, we need the respective probabilities on the RHS of the equation.
From statement I alone, P(White and Even) = 0. No information about P(White) and P(Even).
Statement I alone is insufficient. Answer options A and D can be eliminated. Possible answer options are B, C or E.
From statement II alone, P(White) – P(Even) = 0.2 This is insufficient to find out the value of P(White) + P(Even). Additionally, no information about P(White & Even).
Statement II alone is insufficient. Answer option B can be eliminated. Possible answer options are C or E.
Combining statements I and II, we have the following:
From statement I alone, P(White & Even) = 0
From statement II alone, P(White) – P(Even) = 0.2.
We do not have the value of P(White) + P(Even).
The combination of statements is insufficient. Answer option C can be eliminated.
The correct answer option is E.
Hope that helps!
Aravind B T
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