A box contains nine bulbs out of which 4 are defective. If four bulbs are chosen at random, find the probability that all the four bulbs are defective.
A. $$\frac{{62}}{{63}}$$
B. $$\frac{{125}}{{126}}$$
C. $$\frac{{1}}{{63}}$$
D. $$\frac{{1}}{{126}}$$
Answer: Option D
Solution (By Examveda Team)
Out of nine, five are good and four are defective.Required probability
$$\eqalign{ & = \frac{{{}^4{C_4}}}{{{}^9{C_4}}} \cr & = \frac{1}{{126}} \cr} $$
This Question Belongs to Arithmetic Ability >> Probability
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