<PRE><B>Question 1105169</B>
At first, jane had x marbles and john had y marbles.
The exchange of marbles from jane to john was m marbles.


The description can be turned into system of equations according to the description:
{{{system(x+y=180,y+m=3y,x-m=(1/2)*3y)}}}


{{{system(m=2y,y=2x-3m,x+y=180)}}}


substitute for m,
{{{system(x+y=180,2x=7y)}}}


{{{highlight(y=40)}}}------------john had originally
-
{{{highlight(x=140)}}}-----------jane had at first


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