Question

Find the probability of picking 2 blue marbles when 2 marbles are picked (with replacement) from a bag containing three blue and one yellow marbles

Answer 1

Answer: 0.5

Step-by-step explanation:

Given

There are 3 blue and 1 yellow marble

The chance of picking two marble out of 3 is $^3C_2$

The total no of ways of picking 2 marbles out of 4 is $^4C_2$

Therefore, the probability of picking 2 blue marbles

$\Rightarrow P=\dfrac{^3C_2}{^4C_2}\\\\\Rightarrow P=\dfrac{3\times 2}{4\times 3}\\\\\Rightarrow P=\dfrac{1}{2}$