Question

Find the probability that the birth days of six different persons will fall in exactly two calendar months.

Answer 1

Total cases=`12*12*12*12*12*12=12^6`
Favorable Cases=`.^12C_2[.^6C_1*.^2 2C_1+.^6C_2*.^2C_1+.^6C_3*.^2C_1]`
`P=(.^12C_2[.^6C_1*.^2C_1+.^6C_2*.^2C_1+.^6C_3*.^2C_1])/12^6`.