Question

The probability that a selected two digited number from two digited numbers formed with the digits 1, 2, 3, 4, 5 is without repetition is

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

Answer 1

Answer: (C)

$\frac{4}{5}$

Total numbers $=5\ast 5=25$
The favorable numbers ${=}^5{C}_2\ast 2!=20$
$\Rightarrow P=20/25=4/5$