Question

A bag contains 3 red, 6 white and 7 blue balls. What is the probability that two balls
drawn at random are both white?​

Answer 1

Given,

Total of balls present in bag = 16

16 balls in total out of which 6 white balls present.

Event of taking the first ball as white ball :

P(white) = $\frac{6}{16}$

Event of taking the second ball as white ball :

P(white) = $\frac{5}{15}$                           (15 balls in total and 5 of white balls left)

∴ P(white,white) = $\frac{6}{16} \times\frac{5}{15}$

                             $=\frac{1}{8}$

Thus the probability of getting two white balls is $\frac{1}{8}$.

Answer 2

Answer:

Given question:

• A bag contains 3 red, 6 white and 7 blue balls.

Find:

• What is the probability that two balls drawn at random are both white?

Calculations:

• According to the given question totally there are ($\sf{3 + 6 + 7 = 16}$) bags.

• Out of total 16, there are 6 bags.

• But according to the question we must only find the probability for first two white bags, So for this let's make two equation.

• Let us consider the first ball out of 16 as the white ball so, ($\sf\dfrac{6}{16}$) -Equation-(1).

• As one ball in considered as white in the equation-(1), So the total number of balls would be (16 - 1 = 15)

• Let us consider the second ball out of 15 as the white ball so, ($\sf\dfrac{5}{15}$) - Equation-(2).

Multiplying both the equation 1 & 2:

$\sf=\dfrac{ 6}{16} × \dfrac{5}{15}$

$\sf=\dfrac{1}{8}$

Therefore, 1/8 is the probability that two balls.