The probability of selecting 2 one-rupee coins from a collection of 'a' one-rupee coins and 4 two-rupee coins is 1/3. Determine the probability of randomly choosing a two-rupee coin from a set consisting of (a + 4) one-rupee coins and 2a two-rupee coins.
ATQ, aC2/(a+ 4)C2 = 1/3 Or, {a(a – 1)}/{(a + 4)(a + 3)} = 1/3 Or, 3a2 – 3a = a2 + 4a + 3a + 12 Or, 2a2 – 10a – 12 = 0 Or, 2a2 – 12a + 2a – 12 = 0 Or, 2a(a – 6) + 2(a – 6) = 0 Or, (a – 6)(2a + 2) = 0 Since, the number of coins cannot be negative, therefore a = 6 Number of one rupees coins = a + 4 = 10 Number of two rupees coins = 2a = 12 Total number of coins = 10 + 12 = 22 Required probability = 12/22 = 6/11
Select the correct option that will meet the image pattern of the given image.
Which figure should replace the question mark (?) if the series were to continue?
Identify the figure that completes the pattern.
In each of the following questions, find out which of the answer figures can be formed from the pieces given in the problem figure.
