SOLUTION: Shop A had twice as many laptops as Shop B. After Shop A sold 450 laptops, Shop B had 3 times as many laptops as Shop A. How many laptops did Shop A have at first?

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Shop A had twice as many laptops as Shop B. After Shop A sold 450 laptops, Shop B had 3 times as many laptops as Shop A. How many laptops did Shop A have at first?      Log On


   



Question 965980: Shop A had twice as many laptops as Shop B.
After Shop A sold 450 laptops, Shop B had 3 times as many laptops as Shop A.
How many laptops did Shop A have at first?

Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
ASSIGN VARIABLES
a, how many in shop A
b, how many in shop B
-
a=2b

USE DESCRIPTION
a-450 in store A;
None sold in store B;
3%28a-450%29=b

CREATE EQUATIONS or SYSTEM OF EQUATIONS
system%28a-2b%2C3%28a-450%29=b%29

SOLVE SYSTEM