Juniper

First start with some boolean algebra:
1 and 1 = 1
1 and 0 = 0
0 and 1 = 0
0 and 0 = 0

/24 = 2 x /25 = 4 x /26 = 8 x /27 = 16 x /28 = 32 x /29 = 64 x /30 = 128 x /31 = 256 x /32

/26: 255.255.255.192 = 11111111.11111111.11111111.11000000
/30: 255.255.255.252 = 11111111.11111111.11111111.11111100

/32: 1 IP address within the subnet = 1 host can exist within the subnet
/29: 8 IP addresses within the subnet = 8 hosts can exist within the subnet
/26: 64 IP addresses within the subnet = 64 hosts can exist within the subnet
/25: 128 IP addresses within the subnet = 128 hosts can exist within the subnet
32 = 2^0 = 1
29 = 2^3 = 2x2x2 = 8
26 = 2^6 = 2x2x2x2x2x2 = 64

Interfaces types

whatever you do or fix please test it afterwards, better however do not fix things that work, wait until they break otherwise feel the wrath of dummy users.