Answer:
4.25 km (See Below)
Explanation:
The question is:
How many kilometers did Nathan walk and jog?
Solution:
He walked 1/4th of 5 kilometer race
He jogged 3/5th of 5 kilometers race
Rest, he ran.
We need total km he ran and jog. That is (1/4) + (3/5)th:

So, we find 17/20th of 5, which is:

So, Nathan walked and jogged 4.25 km of the race.