Question

A bag contains 5 black balls, 4 white balls and 3 red balls. If a ball is selected randomwise, the probability that it is a black or red ball is

• A. $\frac { 1 } { 3 }$
• B. $\frac { 1 } { 4 }$
• C. $\frac { 5 } { 12 }$
• D. $\frac { 2 } { 3 }$

Answer 1

Answer: (D)

$\frac { 2 } { 3 }$

Answer 2

P(Black or Red) $= \frac { { } ^ { 5 } C _ { 1 } + { } ^ { 3 } C _ { 1 } } { { } ^ { 12 } C _ { 1 } } = \frac { 2 } { 3 }$.