
Percentages
Hi,
May I be assisted with the following please?
1.) A book was sold for $45 at a loss of 10%. What was the original price?
$\displaystyle 10 \% \times 45 = 4.5$
$\displaystyle \$45 + 4.5 = \$49.5$
$\displaystyle \rm{Original \ Price} = \$49.5$
2.) A man bought a chair for $350. He sold it at a profit of 25%. How much was the selling price?
$\displaystyle 350 \times 0.25$
$\displaystyle = 87.5$
$\displaystyle \rm{Selling \ Price} = 87.5 + \$350 = \$437.50$

Re: Percentages
Edit2: This post was editted after I made a mistake.
1) I think 1 is incorrect.
The man sold the book for $45 which was a 10% loss.
This means that he only sold the book at 90% of the original price.
Which means that $\displaystyle 0.9x=45$ where $\displaystyle x$ is the original price in dollars.
2) Is fine.