H2 Section 2.7: why do you need match metric

[CiscoCCDE]

H2 in section 2.7, I don't understand why we need to configure match metric in R9, R10. Anyone can help me to understand please.

R9/R10
router ospf 1
redistribute eigrp 1 subnets
route-map METRIC permit 10
match metric 10 +- 11
set metric 10000 100 255 1 1500
route-map METRIC permit 20
set metric 1000 100 255 1 1500
router eigrp JACOBS
address-family ipv4 unicast autonomous-system 1
topology base
redistribute ospf 1 route-map METRIC

[Nobita]

we must do it because this question:

Refer to “Diagram 2: Initial Topology” and “Diagram 6: Merge Phase 2”. Jameson’s and Jacob’s are entering in the second phase of the merge and have deployed two new border routers in their respective core network. Configure the core networks as per the following requirements:
• R9 and R10 must run OSPF on their interface Eth0/0 and Loopback 0.
• R9 and R10 must run EIGRP on their interface Eth0/1.
• R53 and R54 must run EIGRP on all of their interfaces.
• Mutually redistribute EIGRP and OSPF on both R9 and R10
• Avoid routing loops and ensure that all current and future prefixes are routed via their optimal path. Do not use any access-list or prefix-list in order to achieve this requirement
• Do not change any administrative distance of any protocol in any router.