Six persons C, D, B, O, N, and P are sitting in a row facing north. Their ages are 6, 12, 15, 18, 27, and 36 years but not necessarily in the same ord...

Six persons C, D, B, O, N, and P are sitting in a row facing north. Their ages are 6, 12, 15, 18, 27, and 36 years but not necessarily in the same order. The following conditions are given:

1. C sits 3rd from one of the ends.
2. The one who is 12 years old sits 2nd to the right of C.
3. The number of persons sitting to the right of the one who is 12 years old is the same as the number of persons sitting to the left of D.
4. O sits 2nd to the right of the one who is 6 years old.
5. Two persons sit between D and B, whose age is twice that of D.
6. N sits to the right of P.
7. The one who is 36 years old sits 3rd to the left of the one who is 15 years old.
8. The age of O is 18 years.

What is the total age of C and B?