Question
40 pens are there in a box where 22 are red pens, ‘p’ are blue pens and remaining are black pens. If a pen is picked, the probability of getting blue pen is 0.25. Find the ratio of the number of blue pens and black pens.
Solution
Probability of getting a blue pen , => p/40 = 1/4 => p = 10 So, number of black pens = 40 – 10 – 22 = 8 Required ratio = 10 : 8 = 5:4
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