Question

It is known that a box of 600 electric bulbs contains 12 defective bulbs. One bulb is taken out at random from this box. What is the probability that it is a non defective bulb. ​

Answer 1

Given as :

The number of bulb in the box = 600

The number of defective bulb in box = 12

Let The probability that one bulb taken out random is non-defective = p(E)

According to question

As out of 600 bulbs, 12 bulbs are defective

So, The number of non-defective bulb = 600 - 12 = 588

Now, out of 600 bulbs, 1 bulb is chosen in {C_{1}}^{600}

And favourable case of chosen non-defective = {C_{1}}^{588}

So, probability = \frac{{C_{1}}^{588}}{{C_{1}}^{600}}

Or, p(E) = \dfrac{588}{600}

Or, p(E) = \dfrac{49}{50}

Hence, The probability that one bulb taken out random is non-defective is \dfrac{49}{50} . Answer