The guest rooms in this hotel all have two windows each. From the second floor upward, all rooms are guest rooms and all windows belong to a room.
The ground floor has no guest rooms, but you can enjoy a fine English breakfast and a cup of Earl Grey.
If all four sides of the hotel have an identical layout, how many guest rooms does the hotel have in total?
UK Version
The guest rooms in this hotel all have two windows each. From the first floor upwards, all rooms are guest rooms and all windows belong to a room.
The ground floor has no guest rooms, but you can enjoy a fine English breakfast and a cup of Earl Grey.
If all four sides of the hotel have an identical layout, how many guest rooms does the hotel have in total?
Hints
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US Version
Take it one floor at a time, starting with the second floor. The number of guest rooms on a floor will equal the number of windows on the floor divided by two.
UK Version
Start by considering the first floor. The number of rooms will equal the number of windows divided by two.
US Version
The number of windows on the sixth and seventh floors is eight per floor.
How many guest rooms is that per floor?
UK Version
The fifth and sixth floors both have eight windows. So, how many rooms are there on each of these floors?
US Version
Every floor from the second to the fifth has 16 windows in total. So how many rooms are there on each of those floors? If you've worked that out, you just need to do the math to get the total number of guest rooms in the hotel.
UK Version
Every floor from the first to the fourth has 16 windows in total. So how many rooms are there on each of those floors? If you've worked that out, you just need to do the arithmetic to get the total number of guest rooms in the hotel.
US Version
If your math really isn't working, try counting all the windows you can see from the second floor upward.
The number of windows you can see is half of the total number, and each room has two windows. If you put these two together, you'll realize that the number of windows you can see on these floors is the same as the total number of guest rooms.
UK Version
If you're having trouble, try counting all the windows that you can see from the first floor upwards.
There are two windows per room, so the number of rooms equals half the total number of windows. And that's exactly how many windows there are on two sides of the hotel.
Just remember that there are no guest rooms on the ground floor.
Solution
Incorrect
Too bad!
US Version
There must be some guest rooms that you forgot to count.
UK Version
Are there any guest rooms you've forgotten to count?
Correct
US Version
Correct!
The hotel has 40 guest rooms.
They must have build the stars and elevators right in the center where there are no windows.
UK Version
Well done!
The hotel has 40 guest rooms.
The stairs and the lift must be in the central part of the hotel, away from the windows.