We can't subnet a network in 30, however it's possible to subnet it in 32. In this case, considering it is an IP Address class C (/24), we have to borrow 5 bitsin the 4th octet, that is, the IP Address203.10.93.0 /24 will turninto203.10.93.0 /29 and mask 255.255.255.248. Dividing the network 203.10.93.0 in 32 it means we will have 8 IP'sper subnet (only 6 of them are valids because the first IP is the Network ID and the last IP is the Broadcast ID, we can't use them).Now let's check out the subnets we'vegot.
1- NID 203.10.93.0
BID 203.10.93.8
2- NID 203.10.93.9
BID 203.10.93.16
3- NID 203.10.93.17
BID 203.10.93.24
4- NID 203.10.93.25
BID 203.10.93.32 And it goes on until 255.
As we can see, the IP 203.10.93.30 is in the 4th subnet and it is not a NID and even a BID, so it is a valid IP address.