Question

a lot of 20 bulbs contains 4 defective ones. One bulb is drawn at random from the lot . What is the probability that the bulb is not defective.

Answer 1

Total Bulb =20
Defective bulbs = 4
Non defective bulbs =20-4=16

P(not defective bulb )=16/20 =4/5

Answer 2

$\frac{4}{20 } = \frac{2}{10 } = \frac{1 }{5}$
1/5 may be. .................