Given: There are 210 rooms in a hotel. All of the rooms are cleaned by housekeepers.
Asked: If each of the housekeepers cleans same number of rooms, how many housekeepers are there?
210 = 2*3*5*7
(1) Each of the housekeepers cleans an odd number of rooms.
If number of rooms = 3; Number of housekeepers = 2*5*7 = 70
But if number of rooms = 5; Number of housekeepers = 2*3*7 = 42
And if number of rooms = 7; Number of housekeepers = 2*3*5 = 30
NOT SUFFICIENT
(2) The number of the housekeepers is greater than the number of the rooms a housekeeper clean.
If number of rooms = 1; Number of housekeepers = 210
If number of rooms = 2; Number of housekeepers = 105
If number of rooms = 3; Number of housekeepers = 70
If number of rooms = 5; Number of housekeepers = 42
If number of rooms = 7; Number of housekeepers = 30
If number of rooms = 10; Number of housekeepers = 21
If number of rooms = 14; Number of housekeepers = 15
NOT SUFFICIENT
(1) + (2)
(1) Each of the housekeepers cleans an odd number of rooms.
(2) The number of the housekeepers is greater than the number of the rooms a housekeeper clean.
If number of rooms = 1; Number of housekeepers = 210
If number of rooms = 3; Number of housekeepers = 70
If number of rooms = 5; Number of housekeepers = 42
If number of rooms = 7; Number of housekeepers = 30
NOT SUFFICIENT
IMO E