Unit rate means how much does it cost for 1 item for example...if you can download 2 songs for $5 how much did it cost to download 1 song...you would simply take $5 divided by 2 to get $2.50
In this case we have 5 yards of fabric for $18 so all we have to do is take $18 divided by 5 to find out how much just 1 yard costs.
so $18 divided by 5 is $3.60 so the unit rate cost per yard is $3.60
to make sure this is correct you can check your answer like this. If it is $3.60 for 1 yard how much would it be for 5 yards? Multiply $3.60 and 5 if we get $18 then our answer is correct. $3.60 x 5 does equal $18 so we were correct