Square pyramid

Calculator

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hexagonal pyramid

Find the lateral area of a regular hexagonal pyramid whose base has sides of length 13.5 cm and which has slant height 8 cm? What is its surface area?
My solution: lateral area 729 cm^2 and surface area= 1202, 9 cm^2. Is this correct?
 
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You got base area = ~474 which is correct...

BUT how did you get 729 as lateral area:confused:

There are 6 triangles with base=13.5 and height = 8, right?

I'm sorry, I gave you the wrong information.:( the slant height should be 18 cm, not 8 and that's how I got 729 . Can you give me a clue how to find the volume, i.e. how to find the height??
 
would height be something like h^2 = 18^2- 11.7^2 --> 11.7 is height of one triangle of the base according to my calculations?
 
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Calculator said:
find the lateral area of a regular hexagonal pyramid whose base has sides of length 13.5 cm

and which has slant height 8 cm?<------ Okay, so you amended the slant height in a later post.

What is its surface area?

My solution: lateral area 729 cm^2

and surface area= 1202, 9 cm^2. <----- Use a decimal point instead. Your tenths place is off.

Is this correct?

Denis said:
You got base area = ~474 <------ Actually, the number of square cm. is closer to 473.

which is correct...


Calculator said:
Can you give me a clue how to find the volume [...] ? Calculator, you should have asked that as part of the original post.

Calculator said:
would height be something like h^2 = 18^2 - 11.7^2 --> 11.7 <------ That's not correct. I don't know if you made a typo
and meant to type 13.7 instead for the height of the pyramid. At that point, I'm not sure if that is the correct rounded
value to the nearest tenths because of too much prior rounding.


is height of one triangle of the base according to my calculations?


Volume of the pyramid = (1/3)*(area of the base of the pyramid)*(height of the pyramid)


First, you have to report the various heights, areas, and volumes, say, correct to the nearest tenths.
Second, but along the way, you can't use rounded heights to one decimal place to get rounded areas
correct to one decimal place. And you can't use both of the above (meaning rounded to one decimal
place) to get the volume rounded correctly to one decimal place.
 
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