Kara drove 36.9 miles before her car broke down. if kara lives 45.55 miles away from work, how much further does she need to travel?

Kara needs to travel 45.55 - 36.9, or 8.65, miles further.

All we need to do to solve this problem is subtract the miles we need to get to work from the miles already traveled

Lets see what we know so far:
We know Kara needs to drive 45.55 miles to get to work.
We know she has already made 36.9 out of the 45.55 miles, so we need to figure out how many are left over. 

To do this, we can subtract:

45.55
-36.9

When we subtract 49.55 from 36.9, we get 8.65.
We can make sure our answer is correct by adding the 8.65 to the 36.9, getting 45.55.

If Kara has already driven 36.9 miles, then she only needs to drive 8.65 more miles to reach the 45.55 miles, which is work!

Hope I could help :)