document.write( "Question 139780: A carpenter goes to a hardware store to buy a specific number of pounds of nails for his business. The first store he enters sells his favorite size nails at 9 cents per pound. At this price, the carpenter realized that he would be short $7.15 if he tried to buy the nails. The carpenter goes to a competing hardware store and finds that the nails sell for 6 cents a pound. He realizes that after paying for the nails, he would have $2.45 left over. How many pounds of nails is he trying to buy? \n" ); document.write( "

Algebra.Com's Answer #101913 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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The first store he enters sells his favorite size nails at 9 cents per pound. At this price, the carpenter realized that he would be short $7.15 if he tried to buy the nails. The carpenter goes to a competing hardware store and finds that the nails sell for 6 cents a pound. He realizes that after paying for the nails, he would have $2.45 left over. How many pounds of nails is he trying to buy?
\n" ); document.write( ":
\n" ); document.write( "Let x = lb of nails required
\n" ); document.write( "Let y = amt of money he has
\n" ); document.write( ":
\n" ); document.write( "Write an equation for each store:
\n" ); document.write( ".09x = y + 7.15
\n" ); document.write( ".06x = y - 2.45
\n" ); document.write( "We can also write it, subtract and eliminate y:
\n" ); document.write( ".09x - y = 7.15
\n" ); document.write( ".06x - y = -2.45
\n" ); document.write( "----------------
\n" ); document.write( ".03x = +9.60
\n" ); document.write( "x = $\"9.6%2F.03\"$
\n" ); document.write( "x = 320 lb of nails
\n" ); document.write( ":
\n" ); document.write( "check solution by finding the cost of each; the dif should be 7.15 + 2.45 = 9.60
\n" ); document.write( "320*.09 = 28.80
\n" ); document.write( "320*.06 = 19.20
\n" ); document.write( "----------------
\n" ); document.write( "differs by 9.60 \n" ); document.write( "

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