Ryan wants to take 5 peanut butter sandwiches to the beach.  If each sandwich consists of 3 slices of bread how many slices does Ryan need to make 5 sandwiches?
To make 1 sandwich, you need 3 slices so Ryan needs 1*3= <<1*3=3>>3 slices to make one sandwich.
Since it takes 3 slices to make a sandwich, and Ryan wants 5 sandwiches to take to the beach he needs 3*5= <<3*5=15>>15 slices.
#### 15