Which block of addresses would be the minimum to accommodate all of these devices if each type of device was on its own network?

Question:
A company has several networks with the following IP address requirements:

IP phones – 50
PCs – 70
IP cameras – 10
wireless access points – 10
network printers – 10
network scanners – 2

Which block of addresses would be the minimum to accommodate all of these devices if each type of device was on its own network?

• 172.16.0.0/25
• 172.16.0.0/24
• 172.16.0.0/23
• 172.16.0.0/22

Explanation: The network for the PCs would require a subnet mask of /25 in order to accommodate 70 devices. That network could use IP addresses 0 through 127. Phones require a subnet mask of /26 for 50 devices (addresses 128-191). Three /28 networks are needed in order to accommodate cameras, APs, and printers. The network scanner network can use a /30. A block of addresses with a mask of /24 will accommodate this site as the minimum amount needed.

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