help with math?

Question

A video game system sold for $135 is discounted 24%. What is the net price?





2. A guitarist earns a royalty of 22% of the seling price of a record album. If he earns $2.64 on each record album sold, What is the selling price of the album?





3.The publisher of Lost in the Jungle recieves $12.60 from each copy sold. The remaining portion of the $15 selling price goes to the author.What royalty rate does the author earn?






4. The creator of a new game recieves a royalty of 8% of the seling price of each game sold. The company that produce the game recieves the remaining amount. if the company recieves $10.10 , per game what is the selling price of the game?

Answer 1

The most complete explanation is to always use ratios and then solve. That way, you just fill in what you know, and solve from there.

%age / 100 = fractional amount / whole amount

Example:
1.) (100% - 24%) / 100 = net price / $135
76/100 = net price / 135
(76/100) * 135 = net price
$102.60 = net price

2.) 22 / 100 = 2.64 / album price
album price = 2.64 * (100/22) = $12

The other 2 work the same way.