12 flawed pens are inadvertently blended in with 132 great ones. It is unimaginable to simply take a gander at a pen and tell whether it is blemished. One pen is taken out aimlessly from this parcel. Decide the likelihood that the pen taken out is a decent one.
12 flawed pens are inadvertently blended in with 132 great ones. It is unimaginable to simply take a gander at a pen and tell whether it is blemished. One pen is taken out aimlessly from this parcel. Decide the likelihood that the pen taken out is a decent one.

Solution:

Quantities of pens = Numbers of blemished pens + Numbers of good pens

∴ Total number of pens = 132+12 = 144 pens

P(E) = (Number of great results/Total number of results)

P(picking a decent pen) = 132/144 = 11/12 = 0.916