a board game question with percents

Question

A board game that normally costs $30 is on sale for 25 percent off. What is the sale price of the game?

Answer 1

Great answer from Arthur, two approaches are useful.

 

Straightforward Option: Just take 25% off the original price and subtract it from the original price. This is exactly what is done at the counter of a store.

 

  $30 - (.25)($30) =

 

  $30 - $7.50 = $22.50 sale price

 

The Option You'll Want to Use From Now On: Note in the first answer you have $30 shown twice. Use the distributive property to back out that $30. It will create a one-step formula you can use for every one of these type of problems:

 

  $30 - (.25)($30) = $30(1 - .25) = $30(.75) = $22.50

 

New Formula:  Orignal x (1 - % off)  = Sales Price

 

Understanding when to use this formula will save you time on regular exams, and high stake exams such as state exams, SAT, PSAT, ACT and math competency exams for jobs and college entrance. It also teaches you to recognize math patterns that payoff in future classes such as Algebra 2, Geometry, Pre-Calculus and Calculus - especially Algebra 2 and Pre-Calculus.

 

I actually learned this formula playing Monopoly as a youngster.

 

Answer 2

$30 game on sale for 25% off

one solution...

25%*$30=0.25*$30=$7.50 off

$30.00-$7.50=$22.50 sale price

another solution...

if the game is 25% off, this means you only pay 75% of $30 (100%-25%=75%)

75%*$30=0.75*$30=$22.50 sale price