Question

What fraction would represent the ratio of the cost

Answer 1

To write 3000 as a fraction you have to write 3000 as numerator and put 1 as the denominator. Now you multiply numerator and denominator by 10 as long as you get in numerator the whole number.
3000 = 3000/1 = 30000/10

And finally we have:
3000 as a fraction equals 30000/10