Question

A drawer contains 4 white socks, 5 black socks, and 3 brown socks. Find the probability that...

... a black sock is selected when a person chooses 1 sock
...a white or brown sock is selected when a person chooses 1 sock.
... a person chooses 3 socks and selects a white first, a black second, and a brown last if the socks are...
...replaced to the drawer.
ii. ..NOT replaced to the drawer.

Answer 1

5/12

7/12

125/36 = 3,47%

50/11 = 4,54%

Explanation:

Probability a black sock is selected when a person chooses 1 sock = 5/12

Probability a white or brown sock is selected when a person chooses 1 sock =

7/12

Probability a person chooses 3 socks and selects a white first, a black second, and a brown last if the socks are replace = (4/12 * 5/12 * 3/12)*100 =125/36 = 3,47%

Pobability a person chooses 3 socks and selects a white first, a black second, and a brown last if the socks are NOT replace = (4/12 * 5/11 * 3/ 10)*100 = 50/11 = 4,54%