What is the answer for question 5) ? http://postimg.org/image/qyfw2lyxj/

Expert Answers
steveschoen eNotes educator| Certified Educator

Hi, lkballer,

There are several ways to do this one.  Let's try this.

If you consider, the original price of the item plus the tax would equal the total cost.  Mathematically, that is:

original cost + taxes = total cost

Now, to calculate taxes, we always multiply the original price by the percent tax.  So, like here, if we have:

x = original price

Then, for the tax, we would have:

taxes = 0.12*x      0.12 stands for 12%, always move the decimal

                                      point 2 places to the left, to get 0.12

So, now, our equation becomes:

x + 0.12x = total cost

We are given the total cost to be $129.40.  So, we have:

x + 0.12x = 129.40

Solving this for x, x+0.12x = 1.12x, so:

1.12x = 129.40

Dividing by 1.12:

x = approx. $115.54

So, the original cost of the item was $115.54.

Good luck, lkballer.  I hope this helps.

Till Then,