IP range in firewall

I am trying to add a custom allow rule in the firewall for a range of IPs from 74.201.102.0 - 74.201.103.255, what exactly am I supposed to enter in the source box? I believe I have to add two separate rules for 102 and 103, and I put /24 at the end of both, is this correct to get the whole range of IPs?

Fortunately for you that range can be summarised as 74.201.102.0/23.

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O.K. great thanks.