Question

There are 12 red balls, 18 blue balls and 6 white balls in a box. When a ball is drawn at random from the box, what is the probability of not getting a red ball?

Answer 1

HINT: - The formula for evaluating probability of any event is
P \[=\dfrac{Favorable\ outcomes}{Total\ outcomes}\] .
Drawing a ball from the bag at random is nothing but taking out a ball without having any bias towards any ball and without having any prior information regarding the balls other than their color.

Complete step-by-step answer:
Now, in the question it is mentioned that there are 12 red balls, 18 blue balls and 6 white balls in the box.
So, the total outcomes for the event of drawing balls at random from the box is
Total outcomes \[=12+18+6\]
Total outcomes \[=36\] .
Now, for favorable outcomes, we need to count the total number of red balls which is given as 12 in the question.
Favorable outcomes \[=12\] .
Now, using the formula for calculating the probability of getting a red ball from the box \[\begin{align}
  & =\dfrac{Favorable\ outcomes}{Total\ outcomes} \\
 & =\dfrac{12}{36} \\
 & =\dfrac{1}{3} \\
\end{align}\]
Hence, the probability of getting a red ball from the box is \[\dfrac{1}{3}\] .

NOTE:Similarly, we can calculate the probability of getting a blue ball or the probability of getting a white ball from the box by using the same formula as mentioned in the hint and the solution as well.
The only difference in the other two probabilities would be that only the favorable outcomes would be changing according to the event.

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