# A flash light has 8 batteries out of which 3 are dead.If two batteries are selected without replacement and tested,the probability that both are dead is

$\begin{array}{1 1}(A)\;\frac{33}{56}\quad(B)\;\frac{9}{64}\quad(C)\;\frac{1}{14}\quad(D)\;\frac{3}{28}\end{array}$

Toolbox:
• oubasict of 8 batteries 3 are dead
• 2 batteries are selected
• without replacement
• p(getting a dead battery)=$$\Large\frac{3}{8}$$
• p(getting second also dead)=$$\Large\frac{2}{7}$$
p(both dead)=$$\Large\frac{3}{8}$$X$$\Large\frac{2}{7}$$
=$$\Large\frac{3}{28}$$
'D'option is correct

edited Mar 15, 2013