SOLUTION: A grocer buys lettuce for $5.20 a crate. Of the lettuce he buys, 10% cannot be sold. If he charges 40 cents for each head he sells and makes a profit of 10 cents on each head he bu

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A grocer buys lettuce for $5.20 a crate. Of the lettuce he buys, 10% cannot be sold. If he charges 40 cents for each head he sells and makes a profit of 10 cents on each head he bu      Log On


   



Question 859959: A grocer buys lettuce for $5.20 a crate. Of the lettuce he buys, 10% cannot be sold. If he charges 40 cents for each head he sells and makes a profit of 10 cents on each head he buys, how many heads of lettuce are in a crate?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
He makes a profit of +10+ cents on each head he buys.
So, he makes a profit of +10+ cents on each head in a crate
Let +x+ = the number of heads in a crate
10% cannot be sold, so he sells +.9x+ heads at +40+ cents each
+.4%2A%28.9x%29+=+.36x+ is what he sells the +.9x+ heads for
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The grocer's profit is +.1x+ ( 10 cents on each head int he crate )
+.36x+-+5.2+=+.1x+
+.26x+=+5.2+
+x+=+20+
There are 20 heads in a crate
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check:
10% can't be sold- that is +.1%2A20+=+2+ heads
He sells +18+ heads at 40 cents each
+18%2A.4+=+7.2+
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His profit is +.1%2A20+=+2+ dollars
+7.2+-+5.2+=+2+
+2+=+2+
OK