How to know the partition where grub is installed

I am Dual Booting Maverick with Natty. I want to know which partition has Grub installed.

I want to make sure that grub is installed in the maverick partition not in natty, so that when I remove the natty partition, I don't have booting problem in the absence of grub.

On maverick there is no menu.list file in /boot/grub but natty has one.

Here is the output of fdisk -l

gaurav@gaurav-desktop:~/Desktop$ sudo fdisk -l

Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x9cdb9cdb

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        7295    58592773+  83  Linux
/dev/sda2            7295       25475   146033664   83  Linux
Partition 2 does not end on cylinder boundary.
/dev/sda3           25476       32194    53970367+  83  Linux
/dev/sda4           32195       35483    26414081    5  Extended
/dev/sda5           32195       32444     1999872   82  Linux swap / Solaris
/dev/sda6           32444       35483    24413184   83  Linux
gaurav@gaurav-desktop:~/Desktop$ 

One way is to run Boot Info Script. It will return the file RESULTS.txt which will include a line similar to:

=> Grub 2 is installed in the MBR of /dev/sda and looks on the same drive in partition #7 for /boot/grub.