SOLUTION: a student 1st reduced a number by 20 % and then increased it again by 20%.if the difference between the two new numbers was 8,then what is the orginal number?

Algebra ->  Customizable Word Problem Solvers  -> Numbers -> SOLUTION: a student 1st reduced a number by 20 % and then increased it again by 20%.if the difference between the two new numbers was 8,then what is the orginal number?      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 889277: a student 1st reduced a number by 20 % and then increased it again by 20%.if the difference between the two new numbers was 8,then what is the orginal number?
Answer by josgarithmetic(39633) About Me  (Show Source):
You can put this solution on YOUR website!
Just follow the process as described!
Let u = the starting number.
20% increase is 1.2u.
20% decrease is 1.2u-0.20%281.20u%29.

The student now has abs%281.2u-%281.2u-0.2u%29%29=8.
abs%281.2u-1.2u%2B0.2u%29=8
abs%280.2u%29=8
0.2u=8
u=8%2F0.2
highlight%28u=40%29