Question

A box contains paper slips with numbers written on them −4 odd and 5 even. Two more paper slips, one with an odd number and another with an even number are put in. Does the probability of getting an odd number increase of decrease? What about the probability of getting an even number?

Answer 1

Initial number of paper slips which have odd number written on them = 4

Initial number of paper slips which have even number written on them = 5

Probability of getting a slip which has odd number written on it

= =

Probability of getting a slip which has even number written on it

==

Number of paper slips added with odd number written on them = 1

Number of paper slips added with even number written on them = 1

Total number of paper slips which have odd number written on them after addition = 5

Total number of paper slips which have even number written on them after addition = 6

Total number of paper slips in the box after addition of slips = 5 + 6 = 11

Probability of getting a slip which has odd number written on it

=

Probability of getting a slip which has even number written on it

=

Initial probability of getting a paper slip which has odd number written on it =

Final probability of getting a paper slip which has odd number written on it =

Initial probability of getting a paper slip which has even number written on it =

Final probability of getting a paper slip which has even number written on it =

From the calculated probabilities, we can observe that the probability of getting a paper slip which has odd number written on it has increased from to and the probability of getting a paper slip which has even number written on it has decreased from to _.