A pair of jeans costs j dollars and is subject to 8% sales tax. Which of the following expression is correct? a)0.08j b)1.08j c)j+8j d)1+0.08j

Question

This is an 8th-grade question that, and is very difficult. A solution and a formula included would be the best response answer.

Answer 1

Since you are looking for the final cost, you are looking for the cost of the jeans plus 8% tax.  8% as a decimal is .08.  If we just took .08 * j, we would get the tax.  We want the tax PLUS the original amount, or j + .08 j.  Whenever we have a variable without a number in front of it, we know it is 1 of that quantity, so if we add j + .08 j we get 1.08 j.  Is that one of your answers?  Then you've got it.

Mary