Ten persons - A, B, C, D, E, F, G, H, I and J were born on either the 7th or 28th of January, March, June, September and December of the same year, but not necessarily in the same order.
B was born in a month of 30 days.
H was born immediate after B and immediate before A.
Neither H nor I was born in September.
| | Case 1 | Case 2 |
Dates | Months | Persons | Persons |
7th | January | | |
28th | | | |
7th | March | | |
28th | | | |
7th | June | B | |
28th | | H | |
7th | September | A | |
28th | | | B |
7th | December | | H |
28th | | | A |
Three persons were born between D and H.
Only two persons were born before C.
| | Case 1 | Case 1a | Case 2 |
Dates | Months | Persons | Persons | Persons |
7th | January | | | |
28th | | D | | |
7th | March | C | C | C |
28th | | | | |
7th | June | B | B | D |
28th | | H | H | |
7th | September | A | A | |
28th | | | | B |
7th | December | | | H |
28th | | | D | A |
Two persons were born between I and D. Thus, case 1 and case 1a are invalid.
| | Case 2 |
Dates | Months | Persons |
7th | January | |
28th | | I |
7th | March | C |
28th | | |
7th | June | D |
28th | | |
7th | September | |
28th | | B |
7th | December | H |
28th | | A |
F, who was born on an odd-numbered date, was born immediate after G.
J was born in January.
| | Case 2 |
Dates | Months | Persons |
7th | January | J |
28th | | I |
7th | March | C |
28th | | |
7th | June | D |
28th | | G |
7th | September | F |
28th | | B |
7th | December | H |
28th | | A |
Therefore, the final arrangement is:
Dates | Months | Persons |
7th | January | J |
28th | | I |
7th | March | C |
28th | | E |
7th | June | D |
28th | | G |
7th | September | F |
28th | | B |
7th | December | H |
28th | | A |
Except option (c), in all other options, only one persons was born between the mentioned two persons.