Where is Singapore fort canning?

Scenario:
I’ll be on business trip to singapore for three days and will only be free on the last day in the morning and leaving to airport at 5pm that afternoon.

I want to do the zoo tour and visit the fort canning as well. I ‘ll be staying at the Rendezvous Hotel and have to be out of the room by 2pm.
I’m thinking of visiting the fort canning first and then go to the zoo since I have to be out of the room by 2 .

So what’s the best way of doing it?

Suggestions:
The afternoon zoo tour comes back at 6.30pm . Since you have leave to the airport at 5pm, do the zoo first in the morning.

The pick up is at 8am and drops you back at the rendezvous hotel around 12pm. You check out then, leave your bags with the bell boys and have your lunch. Go to the fort canning after which is just a short 15 minute walk from your hotel.

Hotels normally have courtesy rooms for shower and change.