If dominik completes a project by himself, it will take him 8 hours. working with katarina, it will take them 5 hours. if they work together, what is the missing value from the table that represents the part of the project dominik will complete? 8r 8(5) r (5)

The main formula we use here is Work=Rate*Time,

1. The rate (speed of working) of Dominik is 



2. Let the the rate of Katarina be 

Together they have a rate of  equal to  (project per hour)

so 

simplify the units:







so the rate of Katarina is 3/40 (proj per hour)

Now, the rate of Dominik was 1/8 (pr/hr)=5/40 (pr/hr)

In 5 hours Dominik complets 5*5/40=25/40 of the project

Katarina completes 5*3/40=15/40 of the project.

Your cleary not see the answer is 25