+0  
 
0
225
1
avatar

Jerry is presently twice as old as his brother and six years older than his sister. How many years from now will Jerry's age be $\frac{2}{3}$ of the combined ages of his brother and sister at that time?

 Apr 3, 2020
 #1
avatar+112280 
+1

 

 

 

Let  Jerry's  brother  now  be   A   years  old

 

Then Jerry's  age  now  =   2A

 

And  his sisters  age  now  =  2A  - 6

 

And  let  x be  the  number of years from now when Jerry's  age  =   (2/3)  combined  age  of his  brother and  sister.....so we  have  that

 

(2A + x)  = (2/3)  [ (A + x)  + ( 2A - 6  +  x  )]     simplify 

 

2A  + (3/2)x =  (2/3)  [ 3A   + 2x  - 6  ]         multiply  through  by 3/2

 

3A  + (3/2)x   =  3A  + 2x  - 6       subtract  3A  from both sides

 

(3/2)x  =  2x  - 6        subtract  2x  from both sides

 

-1/2x =   -6         divide  both sides  by  -1/2

 

x  = 12   years

 

 

cool cool cool  

 Apr 3, 2020
edited by CPhill  Apr 3, 2020

19 Online Users

avatar