Скачать или смотреть Algebra/Word Problems/Lever/Example No. 1-4

e1.) Mary weighted 120 pounds and sat on one end of a teeter-totter 8 feet from the center. Jim weighted 160 pounds and sat on the other side. How far from the fulcrum ( balance point) must Jim to balance Mary if the balance point is at the center of the board? answer: 6 feet

e2.) Tim was digging up his yard to plant a garden. He hit a large rock and got a crowbar to raise the rock to the surface. The crowbar was 6 feet long and the rock was later found to weigh 80 pounds. Tim used other rock as fulcrum and exerted a force equal to 16 pounds on the end of the crowbar in order to raise the rock to a point of balance. How far was the fulcrum from the 80 pound rock? answer: 1 feet

e3.) A weight 60 pounds rest on the end of an 8-foot lever and is 3 feet from fulcrum. What weight must be placed on the other end of the lever to balance the 60 pound weight? answer: 36 pounds

e4.) Four girls decided to use the same teeter-totter. Two of them weighing 50 pounds and 75 pounds, respectively, sat on opposite ends of the 12-foot board which had the balance point at the center. The third girl weighing 60 pounds got on the same side as the weighing 50 pounds and sat 5-feet from the fulcrum. Where must the fourth girl sit so the teeter-totter is balanced if she weighs 40 pounds? answer: 3.75 or 3 3/4 feet.