Question

A bag contains 2 blue, 5 yellow, and 1 black tile. What is the probability of drawing a blue tile followed by a black tile if the first til drawn is not replaced.
A.1/32
B.1/28
C.1/12
D.1/8

Answer 1

Answer:

B.1/28

Step-by-step explanation:

The bag contains 2 blue, 5 yellow, and 1 black tile.

The total number of tiles in the bag is

n(S)=2+5+1

n(S)=8

The number of blue tiles in the bag is

n(B)=2

The number of black tile is

n(Bk)=1

The probability of choosing a blue tiles is

$P(B) = \frac{2}{8} = \frac{1}{4}$

The probability of choosing a black tile without replacing the first tile is:

$P(Bk)= \frac{1}{7}$

The probability of drawing a blue tile followed by a black tile if the first tile drawn is not replaced

$P(B\cap Bk) = \frac{1}{4} \times \frac{1}{7} = \frac{1}{28}$