Section 2.0: Routing Configuration
2.1. Core Routing OSPF/EIGRP/RIP
Configure core routing for all the above protocols on all routers in the network. Redistribute only where necessary; you must use your judgement. See the solutions below where required.
There is a loopback on R3 10.50.13.97/28 in Area66. You will see this route on all participating OSPF routers but not on R5, which is running RIPv1. The RIP network between R5 and R1 is a /27. You are redistributing OSPF into RIP on R1, but it will not redistribute the /28 since it has a different mask belonging to the same major net.
The workaround is to summarize this in RIP on R1 to /27. Since you are restricted not to use a summarization technique, another technique to achieve this ...