Question 301378
Let A be the number of 32 lb boxes.
Let B be the number of 12 lb boxes.
1.{{{A+B=92}}}
2.{{{32A+12B=1604}}}
From eq. 1,
{{{A=92-B}}}
{{{32A=2944-32B}}}
Now substitute into eq. 2,
{{{32A+12B=1604}}}
{{{2944-32B+12B=1604}}}
{{{-20B=-1340}}}
{{{B=67}}}
Then use either equation to solve for A.

{{{A=92-B}}}
{{{A=92-67}}}
{{{A=25}}}
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There are twenty-five 32 lb boxes and sixty-seven 12 lb boxes in the truck.