Question

1. Two forces, 135 pounds and 75 pound are applies to opposite ends of a 14 foot lever. How far from the greater force must the fulcrum be placed so that the lever is balanced?

2. A TV on sale for 772.80 has an orginal price of 996. Find the percent of the markdown.

3. The length of a rectangle is 2 meters longer than twice the width. If the area of the rectangle is 220 m^2, what are then length of the sides?

Answer 1

9514 1404 393

Answer:

1. 5 feet
2. 22.4%
3. 22 m

Explanation:

1. The product of force and distance must be the same for each force. If the distance from the greater force is d, then it is 14-d for the lesser force.

135d = 75(14-d)

210d = 1050

d = 1050/210 = 5

The fulcrum must be placed 5 feet from the greater force.

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2. The percentage change is ...

(772.80/996 -1) × 100% ≈ -22.4%

The TV was marked down about 22.4%.

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3. The product of the two dimensions must be 220 m². We note that 10 and 22 are factors of 220, and that 22 is 2 more than double 10.

The sides are 22 meters long. (The width is 10 m.)