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Let's do this question, a cube of side four centimeter is cut into one centimeter cubes.

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What is the ratio of the surface area of the original cubes and the cubes?

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All right.

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Both the video, give it a try and then let's do it together.

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All right.

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We are back.

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I hope you have given it a try.

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Now, let's start finding the surface area of the initial cube.

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The site is given us four centimeter.

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So we know that the surface area of a cube is six times Saïd Square.

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So the surface area would be six to four square.

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Right.

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All right.

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Now, how many one centimeter cubes can be cut out?

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That would depend on the volume.

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Right now.

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Over here, the volume is forward into four into four.

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So you will get four into four into four cubes of one centimetre cube volume.

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All right.

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Now, what is the surface area of one such cube?

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The side is one centimetre, right?

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We know the surface area is six times the square of the side.

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So the surface area of one such cube would be six into one.

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Right.

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That's the closest centimetre square.

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Now, what's the total surface area?

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You just need to multiply these two together, right?

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So you get the total surface area of the smaller cube is equal to or into four in the four into six.

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All right.

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Now we need to find the ratio of the surface area of the original cube to the race, to the surface

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area.

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Of all the smaller cubes, that would be six in the four square, divided by six in the four cube.

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And that's equal to one by four.

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And that is the answer to this question.

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And that's option C over here.