Question

A bag contains 4 black, 5 red, and 6 pink balls. If 3 balls are selected one after the other without replacement, what is the probability that 3 red balls are chosen?

Answer 1

5/15 * 4/14 * 3/13  = 2/91

Answer 2

Answer:

The probability that 3 red balls are chosen is: 2.2%

Step-by-step explanation:

A bag contains 4 black, 5 red, and 6 pink balls.

Total balls in the bag= 4+5+6= 15 balls in the bag

We need to know what is the probability that 3 red balls are chosen without replacement?

$P_r=\frac{R_b}{T_b}*\frac{R_b-1}{T_b-1}*\frac{R_b-2}{T_b-2}$

Where:

$P_r:$ Probability that 3 red balls are chosen

$R_b:$ Number of red balls

$T_b:$ Number of total balls

$P_r=\frac{5}{15}*\frac{5-1}{15-1}*\frac{5-2}{15-2}\\P_r=\frac{5}{15}*\frac{4}{14}*\frac{3}{13}\\P_r=\frac{1}{3}*\frac{4}{14}*\frac{3}{13}\\P_r=\frac{2}{91}\\P_r=0.022$

$P_r=0.022=2.2$%

The probability that 3 red balls are chosen is: 2.2%