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Let's do this question, a cube of side five centimeter is painted on all its faces if it is sliced

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into one cubic meter cubes.

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How many one cubic meter cubes will have exactly one of their faces painted.

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All right.

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

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All right.

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Let's do it over here.

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The side of the cube is five centimeters, right.

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So if you slice it into one centimeter cube cubes, how many such cubes will you get?

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You will get five to five in the five.

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That's equal to six.

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Twenty five cubes.

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Right.

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Right.

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Over here.

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Say, this is the cube that we started with where the site is five centimeter.

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All right, so it's sliced in two cubes where the side is one centimeter, but this is five centimeters,

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so I need to cut it like this.

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All right, so this one, two, three or five men are learning to do the same thing over here.

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All right, and the same thing over here as well.

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That's how it will look, right?

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And it will come over here as well.

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And this may also.

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OK, so this is how it will look after you slice it up, so we will get five into five into five, that's

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equal to six hundred and twenty five cubes.

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Now, the question says we need to find out how many cubes will have exactly one of their faces painted.

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Now, can you tell me which cubes will have three of their sides painted like these corner cubes?

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For example, over here you have a cube at the corner.

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Right.

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So this part would be painted, this part would be painted and this part would be painted.

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Right.

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So you can see that in the corners, the cube will be painted in three sides, right to the corner.

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Cubes will be painted in three sides.

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What about the edge cubes, for example?

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Let's take this cube.

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So it's not a corner cube, but it is on the edge.

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You can see that for this cube, two sides will be painted, right.

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This side will be painted and the side will be painted.

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So for edge cubes other than corner cubes, two sides will be painted right now.

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Let me draw this surface over here like this.

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Right.

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And these are the corner cubes and these are the edge cubes right now.

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You can see that on each face, the remaining three into three cubes.

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Right.

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So if you remove the edge cubes, right, these you are removing, you will get one, two, three.

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Right.

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One, two, three.

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That's three into three cubes that you have over here.

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Right.

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So that's one, two, three, and one, two, three over here now on each face, the remaining three

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into three cubes will have exactly one side painted, right.

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So in one phase, you will get how many such cubes?

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Nine.

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Three in the tree.

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And how many faces do you have?

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You have six faces right there.

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Therefore, the answer to this question is three into three into six.

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That's equal to fifty four cubes.

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So that is option C over here.