Find Probability Distribution

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written 7.8 years ago by

teamques10 ★ 70k

• modified 3.9 years ago

5 defective bulbs are accidentally mixed up with 20 good ones. It is not possible to just look at a bulb & tell whether the bulb is defective or not. Find the probability distribution of defective bulbs if 4 bulbs are drawn from this lot.

Subject: Applied Mathematics 4

Topic: Probability

Difficulty: Medium

engineering mathematics

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1 Answer

4views

written 7.6 years ago by

teamques10 ★ 70k

Total - 25 bulbs out of which 5 are defective and 20 are good. n= 4

0D	1D	2D	3D	4D
$^20C_4 \times ^5C_0 $	$^20C_3 \times ^5C_1 $	$^20C_2 \times ^5C_2 $	$^20C_1 \times ^5C_3$	$^20C_0 \times ^5C_4 $
4845	5700	1900	200	5

Total number of ways: $ ^{25}C_4 = 126500 $

X=x	0	1	2	3	4
P(X=x)	$\frac{969}{2530}$	$\frac{114}{253}$	$ \frac{38}{253}$	$\frac{4}{253}$	$ \frac{1}{2530}$

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