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 [tex]^3C_2[/tex]
The total no of ways of picking 2 marbles out of 4 is [tex]^4C_2[/tex]
Therefore, the probability of picking 2 blue marbles
[tex]\Rightarrow P=\dfrac{^3C_2}{^4C_2}\\\\\Rightarrow P=\dfrac{3\times 2}{4\times 3}\\\\\Rightarrow P=\dfrac{1}{2}[/tex]
