Can you explain how this answer was arrived at?

Question

I was going over past SAT questions and came across this one:

 

"A furniture store buys its furniture from a wholesaler. For a particular table, the store usually charges its cost from the wholesale plus 75%. During a sale, the store charged the cost from the wholesaler plus 15%. If the sale price of the table was $299, what is the usual price for the table?

A. $359

B. $455

C. $479

D. $524."

 

I understood that I only needed to find 75% of $299 and add the value I arrived at to 299. When I did that, my answer was D.

However, when I looked at the given solution, the answer was B. This is the explanation they gave:

"The sale price of the table was $299. This is equal to the cost from the wholesaler plus 15%. Thus, $299 = 1.15(cost from the wholesaler), and the cost from the wholesaler is $299/1.15 = $260. The usual price is the cost of the wholesaler, $260, plus 75%. Therefore, the usual price the store charges for the table is 1.75 8 $260 = $455, which is B."

 

It's a seemingly simple explanation, but I'm confused. Why do they have to take 15% of the price first? And doesn't 15% = 15/100, not 1.15; and 75% = 75/100 not 1.75? 

 

If you can explain the answer to the question better, please do!

Answer 1

whenever you multiply cost by (1+0.15) you get cost + 15% of the cost; 1.15 represents 100% &15% incorporated into a single multiplier.  Believe me, the SAT book will have accurate explanations.

Answer 2

I think part of what confused you was the 'usually they charge 75,' which is extraneous info. You just needed to worry about the 15, which was the rate for this sale.