Alg3.1.12

From Exampleproblems

If twice the son's age in years is added to the age of his father,the sum is 90.If twice the father's age in years is added to the age of the son,the sum is 120.Find their ages.

Let us assume the age of son is $x\,$

the age of father is $y\,$

Then,twice the son's age in years is $2x\,$

Given,twice the age of son plus ae of father is $90\,$

or $2x+y=90\,$

Similarly, the second condition is $x+2y=120\,$

Solving the two equations

$(2x+y-90)-2(x+2y-120)=0\,$

$2x+y-90-2x-4y+240=0\,$

$-3y+150=0,-3y=-150,y=50\,$

Substituting the value in the first equation,we get

$2x+50=90,2x=40,x=20\,$

Hence,the ages of father and son are $50,20\,$ years

Algebra

Main Page

Retrieved from "http://www.exampleproblems.com/wiki/index.php/Alg3.1.12"

Views

Article
Discussion
View source
History

Personal tools

Create an account or log in

Search

Toolbox

What links here
Related changes
Upload file
Special pages
Printable version
Permanent link

Argan Oil
Natural Skin Care
Organic Skin Care