Bill put his french fries in the oven after it finished heating.  The recommended time was 5 minutes for them to be fully cooked.  He put them in for 45 seconds.  How many seconds remained?
How many seconds are in 5 minutes? ** Each minute last 60 seconds, so that means for the fries to be fully cooked Bill needs to cook them for 5*60=<<5*60=300>>300 seconds
How many seconds are left? ** Since Bill had the fries in the oven for 45 seconds so far, that means they need to stay in the oven for another 300-45= <<300-45=255>>255 seconds.
#### 255