Question

12 defective pens are accidentally mixed with 132 good ones. It is not possible to just
look at a pen and tell whether or not it is defective. One pen is taken out at random from
this lot. Determine the probability that the pen taken out is a good one.​

Answer 1

Answer:

132/144 is the answer ...

Answer 2

Answer:

$\frac{11}{13}$

Step-by-step explanation:

no. of defective pens = 12

no. of  good pens = 132

Total no. of pens = 12 +132 = 144

Probability = $\frac{132}{144}$

                  = $\frac{11}{13}$