I just wonder where people got 60degrees from.
12sides = 12 equal angles
360/12=30degrees

Theflint1:
Clown. I came late to the thread so anything I post as proof would seem like "copy copy." It didn't take me a minute to see the answer though, doesn't require calculations to get the answer.

Now where is your proof that this question baffled Australian students?

i will prove it so you can be the next clown

Theflint1


solution and proof

http://www.unilad.co.uk/news/can-you-solve-the-maths-problem-that-baffled-australian-high-school-students/



https://www.youtube.com/watch?v=gY7BKdNxjeQ

femi4:
close the opened part, it will give you equilateral traingle. 180/3= 60 degrees

Oga if they wanted it closed,they would have done that. You don't have to re-construct the shape,solve for what u were given.

If x = N200 how much is 50 cents? Thank you

Mistake.

EverestdeBliu:
Total angles in a circle = 360 Number of sides = 12 X = 360 ÷ 12 X = 30 Therefore,angle x is equals 30 degrees.

x is twice if u produce the inclination angle. x=2×30=60

nawtibownie:
That area forms an equilateral triangle (three equal sides.) Each angle of a triangle is 60°.
X= 60°

i bet dis babe sabi wuruwuru to d answer...........





where did u see equilateral triangle

this is 12 sided polygon called dodecagon.
a dodecagon has an interior angle size of 150degrees (fact)
using the diagram, angle on the red straight line is i80
180 - 150 on one of the coin is 30 30 to the red line
and same to the other coin.
30 + 30 = 60degree
Final answer = 60degrees

fippycbk:


Good man. Although I can use another approach to arrive at same answer

Yeah True,

since it is a Regular polygon with 12sides, the length of each side is equal.

The last line of the central triangle could be got by rolling over either coin as their vertices are parallel to each other. Thus, the central triangle becomes an equilateral triangle.

The angle in an equilateral triangle = 60

I wonder where pple t getting an equilateral triangle.
All d stody os just paparazi meant to distract and confuse d student.
What d qtn is all about is d value of d angle of one side of d coin which is simply 30 degs.
360/12= 30.

I wonder where pple r getting an equilateral triangle.
All d story is just paparazi meant to distract and confuse d student.
What d qtn is all about is d value of d angle of one side of d coin which is simply 30 degs.
360/12= 30.

Its 60 degree

X=30...I fink d second coin is juz thr to confuse cos d red line only piont one acute angel

ibrutex:



i bet dis babe sabi wuruwuru to d answer...........





where did u see equilateral triangle

Brother, there is no wuruwuru to the answer. There is your equilateral triangle. If you were an engineering/architectural student, you would understand geometry. Even the Egyptians used common sense to gauge their pyramids before Greek mathematicians came up with PYTHAGORAS THEOREMS.

had it been an irregular polygon with uneven sides, then this theory would not hold water but
since it is a Regular polygon with 12sides, the length of each side is equal. and as such their vertices would always be parallel to each other.

The last line of the central triangle could be got by rolling over either coin as their vertices are parallel to each other. Thus, the central triangle becomes an equilateral triangle.

The angle in an equilateral triangle = 60

However, for an irregular polygon, a whole lot of bisecting and "pythagorisations" would be needed

EverestdeBliu:
Oga if they wanted it closed,they would have done that. You don't have to re-construct the shape,solve for what u were given.

You know nothing about geometry.
Don't say this outside again....you must be shallow in mathematical knowledge.

The bolded shows that your mathematical foundation is faulty

predatorX:


Brother, there is no wuruwuru to the answer. There is your equilateral triangle. If you were an engineering/architectural student, you would understand geometry. Even the Egyptians used common sense to gauge their pyramids before Greek mathematicians came up with PYTHAGORAS THEOREMS.

had it been an irregular polygon with uneven sides, then this theory would not hold water but
since it is a Regular polygon with 12sides, the length of each side is equal. and as such their vertices would always be parallel to each other.

The last line of the central triangle could be got by rolling over either coin as their vertices are parallel to each other. Thus, the central triangle becomes an equilateral triangle.

The angle in an equilateral triangle = 60

However, for an irregular polygon, a whole lot of bisecting and "pythagorisations" would be needed

You even have time in explaining to them. There foundation in mathematics is very poor

EverestdeBliu:
Oga if they wanted it closed,they would have done that. You don't have to re-construct the shape,solve for what u were given.

lol, now i know that some people just went to school with "FOODBAGS" instead of "SCHOOLBAGS".

Pls, don't ever say this outside oooo!!! In the world of geometry, you can re-construct a specimen to the "edge of the universe", no holds barred affair.

EverestdeBliu:
where did u see the 'equilateral triangle'?

No mind am,na alomo dey em eye

iyke2ken:


Lol... Pls can you solve from a carpenter's perspective? Sebi it is different answers for different professions?

you funny, Ask those getting 30 degrees, that's the Carpenter's perspective.....lol.

proudly9ja:


A circle has infinite number of sides

Seconded!!

femi4:
You know nothing about geometry.
Don't say this outside again....you must be shallow in mathematical knowledge.

The bolded shows that your mathematical foundation is faulty

predatorX:


lol, now i know that some people just went to school with "FOODBAGS" instead of "SCHOOLBAGS".

Pls, don't ever say this outside oooo!!! In the world of geometry, you can re-construct a specimen to the "edge of the universe", no holds barred affair.

this doesn't change the answer from 30deg'. Mind you,even while "re-constructing",u don't contrast or expand the shape,but draw some segmented/imaginary lines to get definite shapes or angles to ease your working,and these extensions must be guided with geometrical rules. The kind of re-construction u recommended above is flawed.

U go fear answers! smh. anyways 2 diff methods same answers.
method 1.
sum of angles in a circle= 360°.
no. of sides = 12,
x= 360/12=30°

method 2.
sum of interior angles in a polygon= (n-2)180
n is no. of sides=12
= (12-2)180
=10(180)= 1800
angle of 1 interior.= 1800/12=150°
(wsh i cud draw d triangle formed but cant.)
from d triangle,1 of d angles=150/2=75°
sum of the angles of the triangle= (75+75+x)=180°
therefore, x=180°-(75+75)°
x=30°.

EverestdeBliu:







this doesn't change the answer from 30deg'. Mind you,even while "re-constructing",u don't contrast or expand the shape,but draw some segmented/imaginary lines to get definite shapes or angles to ease your working,and these extensions must be guided with geometrical rules. The kind of re-construction u recommended above is flawed.

I m sorry, you are not scientific enough for us to have this conversation. I can't begin to tell you many reasons why the angle can't be 30 degrees especially by inspection and construction.

ptolemy247:


You got the answer but you missed the method
The number of angles in a 12-sided polygon is (n-2)*180~(12-2)*180=1800.
When you divide 1800 by 12, you have 150 equal interior angles.
However, a theory states that the sum of the interior angle and the opposite exterior angle is equal to 180. So 180-150=30
For both polygons, you have 30*2=60 Q.E.D

I think my method is derived from first principles, but you used derived theorems. Its all ok, so long as one can remember the theorems. If not its always good to be able to derive them again from the first principles.

femi4:
I m sorry, you are not scientific enough for us to have this conversation. I can't begin to tell you many reasons why the angle can't be 30 degrees especially by inspection and construction.

No conversation is needed here. Accept the obvious facts and move on. Goodnight

I did this in primary 1V, back in the days.
Australians must be dull in mathematics.
60 degrees.

itstpia8:
no crashes, thanks.

is X the angle between the two radii if it is it's 30 but if it is the sum of those external angles of the polygon it is 60

is X the angle between the two radii if it is it's 30 but if it is the sum of those external angles of the polygon it is 60

EverestdeBliu:
Total angles in a circle = 360
Number of sides = 12
X = 360 ÷ 12
X = 30
Therefore,angle x is equals 30 degrees.

my thoughts exactly. But i think you are referring to a different angle.

If diz was gmaths or gre 30 is a trap ans.... n btw someone already posted a video of d workings... so y re sum pple getting worked up n even declaring certificates, engineers, carpenters n mathematicians n statistician una doh oooo...

shiiit didnt even take me two mins. ans is 60