Can it be a wrong given CIDR?

Am given some homework about creating 4 sub-nets out of a network address of 198.77.48.0/23. Clearly this is a class C address but can it even be possible to have a CIDR /23? We took it otherwise and thought our tutor might have errored. That in order to create 4 sub-nets, we actually need a /26. In that way, we get the following sub-nets

Network addresses

198.77.48.0 -> 198.77.48.64 -> 198.77.48.128 -> 198.77.48.192

Hosts addresses : From

198.77.48.1 -> 198.77.48.65 -> 198.77.48.129 -> 198.77.48.193

Hosts addresses To

198.77.48.62 -> 198.77.48.126 -> 198.77.48.190 -> 198.77.48.254

Broadcast addresses

198.77.48.63 -> 198.77.48.127 -> 198.77.48.191 -> 198.77.48.255

Solution

I think i finally got the answer. This is like sub-netting an already sub-netted network.