Surface area
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Surface area
Hi,
Feel bit daft posting this my daughter missed 2 weekly maths lessons at school as she was rehearsing for Xmas concert, the teacher gave her homework sheet 1st week to try which she done it hasn't been marked yet , then 2nd week homework was set online , when she done online work it's marks instantly and they were wrong so here goes......
Work out surface area of toblerone
Each piece (triangle) is 4cm width 4cm height - 1cm depth
Their is 12pieces
So please correct me if wrong triangle 4x4=16 divide by 2 so surface area of triangle front and end is 16 then sides are 4x12=48 x3 = 144 + 16= 160
Does this sound correct?
Thanks in advance x
Feel bit daft posting this my daughter missed 2 weekly maths lessons at school as she was rehearsing for Xmas concert, the teacher gave her homework sheet 1st week to try which she done it hasn't been marked yet , then 2nd week homework was set online , when she done online work it's marks instantly and they were wrong so here goes......
Work out surface area of toblerone
Each piece (triangle) is 4cm width 4cm height - 1cm depth
Their is 12pieces
So please correct me if wrong triangle 4x4=16 divide by 2 so surface area of triangle front and end is 16 then sides are 4x12=48 x3 = 144 + 16= 160
Does this sound correct?
Thanks in advance x
Re: Surface area
The sides are not all 4cm long according to this, though - the base is 4cm and the height is 4cm, which makes the two other sides 4.472cm (possibly rounded to 4.5cm here)Morgan0210 wrote:Work out surface area of toblerone
Each piece (triangle) is 4cm width 4cm height - 1cm depth
Their is 12pieces
So please correct me if wrong triangle 4x4=16 divide by 2 so surface area of triangle front and end is 16 then sides are 4x12=48 x3 = 144 + 16= 160
Does this sound correct?
B is the length of the base: 4
A is the altitude (height): 4
L is the length of either of the other two sides
L = Square root of ((A squared) plus (half B, squared))
= Square root of (16 + 4)
(Sorry, can't work out how to do the notation).
So the perimeter of each face is B + L1 + L2 (4 + 4.5 + 4.5) = 13cm, not 12cm.
Or 12.944cm...
Outside of a dog, a book is a man's best friend. Inside of a dog it's too dark to read.Groucho Marx
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Re: Surface area
Is the toblerone unwrapped...ie work out area of each bit and x 12 rather than in its box? Plus toadie is right, the sides of the triangles are not 4, that is the perpendicular height
If I were you I would definitely buy one so you can both visualise it....and then scoff the lot
If I were you I would definitely buy one so you can both visualise it....and then scoff the lot
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Re: Surface area
That is a fairly rubbish question, too many assumptions need to be made.. Just eat it
Re: Surface area
Look on the bright side, at least the question totally ignores the bit of chocolate the triangles are joined to at the bottom...
Outside of a dog, a book is a man's best friend. Inside of a dog it's too dark to read.Groucho Marx
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Re: Surface area
And that they have curves...
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Re: Surface area
As do I....after all that chocolate....!!!