Question 37663
On a fishing trip, Mariko caught twenty-four fish. Sh caught some rockfish averaging 2.5 lb. and some bluefish averging 8 lb. The total weight of the fish was 137 lb. How many of each kind of fish did she catch?
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Define variables:
b=number of bluefish
r=number of rockfish
Equations:
{{{b+r=24}}}
{{{2.5r+8b=137}}}
Combine:
{{{-8b-8r=-192}}}
+
{{{2.5r+8b=137}}}
=
{{{-5.5r=-55}}} so {{{r=10}}}
Plug in:
{{{b+r=24}}}
{{{b+10=24}}}
{{{b=14}}}