Question 1113921
Jill has x marbles.
Jack has  3x-5 marbles.


Together Jack and Jill have  23 marbles, given.

{{{(3x-5)+x=23}}}

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Solve that equation for x and evaluate 3x-5.
{{{3x-5+x=23}}}
{{{3x+x=23+5}}}
{{{4x=28}}}
{{{highlight(x=7)}}}-----------Jill has 7 marbles.


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{{{3*7-5}}}
{{{21-5}}}
{{{highlight(16)}}}-------------Jack has 16 marbles.