Question
A box consists of 125 apples out of which 25 are rotten.
Khushboo comes to buy non-rotten apple. The shopkeeper takes out two apples and hands it over to Khushboo one after another. If the apple is not rotten she buys else the shopkeeper keeps them back. What is the probability that Khushboo buys at least one apple?Solution
Case I: Khushboo buys two apples
Probability of buying first apple = (125 - 25)/125 = 100/125 = 4/5
Probability of buying second apple = (100 - 1)/(125 - 1) = 99/124
∴ Probability of buying two apples = (4/5) X (99/124) = 99/155
Case II: Khushboo buys one apple
Probability that she is offered non-rotten apple in first attempt and rotten in second = 100/125 X 25/124 = 5/31
Probability that she is offered rotten apple in first attempt and non - rotten in second = 25/125 X 100/125 = 4/25
∴ Required Probability = 99/155 + 5/31 + 4/25 = 24/25
Prathama Bank was sponsored by SBI
Hornbill Festival is associated with which state?
Income recognition and provisioning guidelines were introduced by RBI in-
Which of the following is the largest organ of the United Nations?
In 1960, _____________, a World Bank arm was established to serve as the Bank's concessional lending arm and provide low and no-cost finance and grants ...
Match the following:
UTI was the first private sector Mutual Fund in IndiaÂ
Which international financial institution did NABARD collaborate with to set up a carbon fund to address climate risks?
When is World Food Day celebrated?
Garima Grehas are primarily established to benefit which of the following groups?
Relevant for Exams:
