Quantitative Reasoning question

[predentgal]

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A scale model of a bridge is made of the same materials a real bridge will be, in the same proportions, and weighs 10 pounds. If an inch in the model (in any dimension) represents 100 inches on the real bridge, how much
will the real bridge weigh?

a 1 x 10^3
b 1 x 10^ 4
c 1X 10 ^5
d 1 x 10^ 6
e 1 x 10^7

I set up a proportons and got A as the answer but the answer is E.. I don't get it🙁

 

[hausee]

A scale model of a bridge is made of the same materials a real bridge will be, in the same proportions, and weighs 10 pounds. If an inch in the model (in any dimension) represents 100 inches on the real bridge, how much
will the real bridge weigh?

a 1 x 10^3
b 1 x 10^ 4
c 1X 10 ^5
d 1 x 10^ 6
e 1 x 10^7

I set up a proportons and got A as the answer but the answer is E.. I don't get it🙁

just image the bridge is a box. every side of box is now 100 times of the model. so the volume will be 100*100*100 times of the model. since model is only 10 lbs, total weight of the real bridge is 100*100*100*10=10^7

 

[predentgal]

How do you know that its dimensional though?

 

[Streetwolf]

How do you know that its dimensional though?

I think it's safe to say a bridge is 3 dimensional.

Remember that weight is based off of the entire object which is 3D. So you need to consider all 3 dimensions.