Algebra word problem

Question

Scores on the act rose from 20.8 in 2002  to 21.1 in 2009 what % increase was this to the nearest tenth of a percent?

Answer 1

Hi Robert,

 

The first thing to do is determine the actual amount of increase. Since the scores rose from 20.8 to 21.1, the amount of increase was 21.1 - 20.8 or 0.3.

 

Now the question what percent of the ORIGINAL score (20.8) is 0.3.

 

That would be determined by 0.3/20.8 which to 4 decimal places would be 0.0144. Of course that is not a percentage. Divide by 100 to convert to percent, giving 1.44% (or to the nearest tenth 1.4%).

 

part is to whole as x% is to 100%.

 

.3/20.8 = x%/100%

 

So, x% = .3(100%)/20.8

 

The above illustrates a way to visualize how to find what percent .3 is of 20.8.