Lecture-12: Baye's Theorem…..cont.…
Wednesday, December 23, 2020 6:30 PM
EXAMPLE 4 : An insurance company insured 2000 scooter drivers, 4000 car drivers and 6000 truck drivers. The
probabilities of an accident involving a scooter driver, car driver and a truck driver are 0.01, 0.03 and 0.15
respectively. One of the insured person meets with an accident. What is the probability that he is a scooter
driver?
EXAMPLE 5 : urn A contains 2 white, 1 black and 3 red balls, urn B contains 3 white, 2 black and 4 red
balls and urn C contains 4 white, 3 black and 2 red balls. One urn is chosen at random and 2 balls are
drawn at random from the urn. If the chosen balls happen to be red and black, what is the probability that
both balls come from urn B?
PROBABILITY Page 1
, EXAMPLE 7 : A card from a pack of 52 cards is lost. From the remaining cards of the pack 2 cards are drawn and
are found to be hearts. Find the probability of the missing to be a heart?
• EXAMPLE-8: Suppose a girl throws a die. If she gets a 5 or 6, she tosses a coin three times and notes the
number of heads. If she gets a 1, 2, 3, or 4, she tosses a coin once and notes whether a head or tail is
obtained. If she obtained exactly one head; what is the probability that she threw a 1, 2, 3, or 4 with the die?
PROBABILITY Page 2
Wednesday, December 23, 2020 6:30 PM
EXAMPLE 4 : An insurance company insured 2000 scooter drivers, 4000 car drivers and 6000 truck drivers. The
probabilities of an accident involving a scooter driver, car driver and a truck driver are 0.01, 0.03 and 0.15
respectively. One of the insured person meets with an accident. What is the probability that he is a scooter
driver?
EXAMPLE 5 : urn A contains 2 white, 1 black and 3 red balls, urn B contains 3 white, 2 black and 4 red
balls and urn C contains 4 white, 3 black and 2 red balls. One urn is chosen at random and 2 balls are
drawn at random from the urn. If the chosen balls happen to be red and black, what is the probability that
both balls come from urn B?
PROBABILITY Page 1
, EXAMPLE 7 : A card from a pack of 52 cards is lost. From the remaining cards of the pack 2 cards are drawn and
are found to be hearts. Find the probability of the missing to be a heart?
• EXAMPLE-8: Suppose a girl throws a die. If she gets a 5 or 6, she tosses a coin three times and notes the
number of heads. If she gets a 1, 2, 3, or 4, she tosses a coin once and notes whether a head or tail is
obtained. If she obtained exactly one head; what is the probability that she threw a 1, 2, 3, or 4 with the die?
PROBABILITY Page 2
