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put this solution on YOUR website!"Jones and Smith together weigh 340 pounds" __ J+S=340 __ J=340-S
"they balance a lever when Jones sits 5 feet from its fulcrum on one side and Smith sits 6 feet from the fulcrum on the other side"
when they balance, the products of their weights and distances from the fulcrum are equal __ 5J=6S
substituting __ 5(340-S)=6S __ 1700-5S=6S __ 1700=11S __ 1700/11=S
substituting __ J=340-(1700/11) __ J=2040/11