I'm learning ipv4 subnetting and would like to gain more understanding of the following answer

I have two examples, first one I worked out, the second I struggle with.

For the first example, I am given the following address:

172.153.75.250/25 

I have to find the:

• Network
• First Host
• Last Host
• Broadcast
• Next Subnet

Given the above address, I work out that the Subnet Mask is 255.255.255.128.

I get there by looking at CIDR of /25. 8+8+8+1

With the subnet mask of 255.255.255.128:

• 172.153.75.128 is the network
• .129 is the first host
• .254 is the last host
• 255 is reserved for broadcast
• Next subnet would start at 172.153.76.0

I understand the above and it makes sense. Here is the second example:

65.6.23.194/14 

Following my logic from the first example, /14 translates to a subnet mask of 255.252.0.0 . if it was 255.255.0.0 then network would be at 65.6.0.0, but since the second mask octet is 252, the network is also two less at 65.4.0.0.

First host is 65.4.0.1

I thought that the last host would be 65.6.255.254 and broadcast would be 65.6.255.255 , with next subnet starting at 65.7.0.0. Unfortunately the last host, broadcast and next subnet are incorrect.

Could someone please explain to me why last host is 65.7.255.254 and not 65.6.255.254? Once I understand that, I should be able to work out why the broadcast and next subnet are what they are.

Thank you!