Question

Find the total cost of producing 5 widgets

Answer 1

If it takes $670 to produce 10 widgets and you are looking for the cost of 5 it is half of ten so you do  $670/2 = 335

So 335 is your answer 

Answer 2

670/c = 10/5

Let c = cost for 5 widgets

10c = 670(5)

10c = 3350

c = 3350/10

c = 335