Since there are 10 balls in the first bag out of which 6 are red and 4 are blue.
Suppose that A has occurred. Then a red ball is transferred into second bag. The probability of getting a red ball from the second bag when a red ball is got from the first is P (C/A) = 5/11
The probability of getting a red ball from the first bag and a red ball from the second is
Now,
suppose the event B has occurred then a blue ball is transferred
into the second bag. There are now 11 balls in the second bag out
of which 4 are red.
Since A Ç
C and BÇ C are mutually
exclusive events
Example In a certain school, 25% of the
boys and 10% of the girls are studying French. The girls constitute
60% of the students boy. If a student is selected at random and
is studying French, determine the probability that the student is
a girl.
Solution : Let there be 100 students. 60% of which are
girls.
i.e. number of girls is 60 and number of boys is 40.
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