In 22.214.171.124/16 There are 2^16=65536 IP Addresses available
In group 1 total IP address allocated is 128*64=8192 IP
in group 2 total IP address allocated is 64*256=16384 IP
In group 3 total IP address allocated is x*y=xy IP
ISP has 38K IP address left = 38912 IP
so group 3 has IP address = Total IP addresses - (group 1 IP addresses+ group 2 IP addresses)
$so$ $possible$ $value$ $of$ $x$, $y$ is $64$, $32$
@prashant281188 kindly tell me here how you interpret meaning of 38K as 38×1024 and not as 38×1000.plzz reply.
@Shreya kumari because in IP address allocation we can allocate IP addresses in power of 2's only.