Question

Suppose you choose a marble from a bag containing 2 red marbles, 5 white marbles and 3 blue marbles. You return the first marble to the bag and choose again. Find p (red then blue)

Answer 1

I think it would be 2/10 x 3/10=6/100=3/50

Answer 2

Answer:   $\frac{3}{50}$

Step-by-step explanation:

Given: Number of red marbles = 2

Number of white marbles = 5

Number of blue marbles  = 3

Total marbles =2+5+3=10

If we choose first marble from the bag, then the probability of having red marbles will be :-

$P(R)=\frac{2}{10}=\frac{1}{5}$

If we choose second marble after replacement (total remains same) from the bag, then the prob ability of having blue marbles will be :-

$P(B)=\frac{3}{10}$

Since, both the events are independent.

Therefore, the probability of choosing red marble then blue marble is given by :-

$\text{P(red then blue)}=P(R)\times P(B)=\frac{1}{5}\times\frac{3}{10}=\frac{3}{50}$