You have a class A network address 10.0.0.0 with 40 subnets, but are required to add 60 new subnets very soon. You would like to still allow for the largest possible number of host IDs per subnet. Which subnet mask should you assign?

You have a class A network address 10.0.0.0 with 40 subnets, but are required to add 60 new subnets very soon. You would like to still allow for the largest possible number of host IDs per subnet. Which subnet mask should you assign?

We cannot take 100 subnets,it would be minimum 128(2^7) subnets because 64 will not suffice.So in the subnet mask,we need to mask 7 more bits than in any class A IP address.so the subnet mask becomes 11111111.11111110.00000000.00000000 i.e 255.254.0.0

Pls share the solution