Answer :
You'd fine the unit rate, in the context of the problem it would be how many minutes it takes for 1 pizza to cook
20/4= 5 minutes for 1 pizza
we are finding how long it would take to cook 10
5 times 10= 50, so 50 minutes
20/4= 5 minutes for 1 pizza
we are finding how long it would take to cook 10
5 times 10= 50, so 50 minutes