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Arnold Benches & Builds and Equation

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The bar weighs 45 pounds.

45

3 of 13

The bar weighs 45 pounds.

45

He puts a 45 pound plate on each side of the bar.

45 + 2 ( 45 )

4 of 13

The bar weighs 45 pounds.

45

He puts a 45 pound plate on each side of the bar.

45 + 2 ( 45 )

He puts a 10 pound plate on each side of the bar.

45 + 2 ( 45 + 10 )

5 of 13

The bar weighs 45 pounds.

45

He puts a 45 pound plate on each side of the bar.

45 + 2 ( 45 )

He puts a 10 pound plate on each side of the bar.

45 + 2 ( 45 + 10 )

He puts clamps on each side to hold the weights, but he doesn’t know how much they weigh.

45 + 2 ( 45 + 10 + c )

6 of 13

The bar weighs 45 pounds.

45

He puts a 45 pound plate on each side of the bar.

45 + 2 ( 45 )

He puts a 10 pound plate on each side of the bar.

45 + 2 ( 45 + 10 )

He puts clamps on each side to hold the weights, but he doesn’t know how much they weigh.

45 + 2 ( 45 + 10 + c )

Just for fun, he balances one clip in the middle of the bar.

45 + 2 ( 45 + 10 + c ) + c

7 of 13

The bar weighs 45 pounds.

45

He puts a 45 pound plate on each side of the bar.

45 + 2 ( 45 )

He puts a 10 pound plate on each side of the bar.

45 + 2 ( 45 + 10 )

He puts clamps on each side to hold the weights, but he doesn’t know how much they weigh.

45 + 2 ( 45 + 10 + c )

Just for fun, he balances one clip in the middle of the bar.

45 + 2 ( 45 + 10 + c ) + c

The total weight is 170 pounds.

45 + 2 ( 45 + 10 + c ) + c = 170

8 of 13

How many pounds does each clamp weigh?

45 + 2 ( 45 + 10 + c ) + c = 170

170 lbs

=

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How many pounds does each clamp weigh?

45 + 2 ( 45 + 10 + c ) + c = 170

Multiply the weight of the plates and clamps since there is one of each on each side.

45 + 90 + 20 + 2c + c = 170

170 lbs

=

10 of 13

How many pounds does each clamp weigh?

45 + 2 ( 45 + 10 + c ) + c = 170

Multiply the weight of the plates and clamps since there is one of each on each side.

45 + 90 + 20 + 2c + c = 170

Combine the weight of the bar and plates.

155 + 2c + c = 170

170 lbs

=

11 of 13

How many pounds does each clamp weigh?

45 + 2 ( 45 + 10 + c ) + c = 170

Multiply the weight of the plates and clamps since there is one of each on each side.

45 + 90 + 20 + 2c + c = 170

Combine the weight of the bar and plates.

155 + 2c + c = 170

Combine the weight of the three clamps, 3c.

155 + 3c = 170

170 lbs

=

12 of 13

How many pounds does each clamp weigh?

45 + 2 ( 45 + 10 + c ) + c = 170

Multiply the weight of the plates and clamps since there is one of each on each side.

45 + 90 + 20 + 2c + c = 170

Combine the weight of the bar and plates.

155 + 2c + c = 170

Combine the weight of the three clamps, 3c.

155 + 3c = 170

-155 -155

Subtract the weight of the plates and bar from the total weight.

3c = 15

15 lbs

=

13 of 13

How many pounds does each clamp weigh?

45 + 2 ( 45 + 10 + c ) + c = 170

Multiply the weight of the plates and clamps since there is one of each on each side.

45 + 90 + 20 + 2c + c = 170

Combine the weight of the bar and plates.

155 + 2c + c = 170

Combine the weight of the three clamps, 3c.

155 + 3c = 170

-155 -155

Subtract the weight of the plates and bar from the total weight.

3c = 15

3 3

Divide the remaining weight by three to find that each clamp weighs five pounds.

C = 5

5 lbs

=