প্রশ্ন সংশোধন করুন
প্রশ্ন:
a box contains 20 electric bulbs , out of which 4 are defective . 2 bulbs are chosen at random from this box . The probability that at least one of these is defective is
a box contains 20 electric bulbs , out of which 4 are defective . 2 bulbs are chosen at random from this box . The probability that at least one of these is defective is