JEE Main 2019 — Probability Question with Solution
From: JEE Main 2019 (Online) 12th January Evening Slot
Question
In a game, a man wins Rs. 100 if he gets 5 or 6 on a throw of a fair die and loses Rs. 50 for getting any other number on the die. If he decides to throw the die either till he gets a five or a six or to a maximum of three throws, then his expected gain/loss (in rupees) is :
Choose an option
Show full solutionCorrect option: B
Correct answer
B0
Step-by-step explanation
Expected Gain/Loss =
= w 100 + Lw( 50 + 100)
+ L2w ( 50 50 + 100) + L3( 150)
=
here w denotes probability that outcome 5 or 6 (w = )
here L denotes probability that outcome
1,2,3,4 (L = = )
= w 100 + Lw( 50 + 100)
+ L2w ( 50 50 + 100) + L3( 150)
=
here w denotes probability that outcome 5 or 6 (w = )
here L denotes probability that outcome
1,2,3,4 (L = = )
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This is a previous-year question from JEE Main 2019, covering the Probability chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.