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Maths, Addmaths and Statistics: Post your doubts here!

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@Add Maths students: Plz help.
Q. A sports club wishes to use 720 m of fencing to make six equal-sized rectangular courts placed adjacent to each other as shown in the diagram. Given that each court measures x m by y m, show that the total area of all six courts, A m^2, is given by A=3/4(720x-9x^2). Given that x and y may vary, find the dimensions of each court for which A is a maximum.
I have no clue at all to how to solve this question......:(
 
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please please anyone explain me:
q7)a) http://www.xtremepapers.com/papers/...(Calculator Version) (4024)/4024_s03_qp_2.pdf
wat frmulas will b applied? please....


The marks say it all don't they ? :p
its a long question ..

Cylinder Part.
you will first take the surface area of the cylinder .. 2πr(h+r) then subtract πr^2 from it (cuz one end of cylinder is not there, as its an open cylinder) Now divide it by two because the cylinder is half filled.

Hemisphere part.

Find hemisphere's surface area with the formulae 2πr^2 .. (cuz the hemisphere is open ended too..) divide it by two (half filled.)

Add them both .. and you got yourself an answer. :)
 
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just make each of its prime factors' power even and you're done.

2^3*3*7

make them go to the next power which is even..

2^4*3^2*7^2

so what did you multiply it with to get the above?

2*3*7 = Your Answer.
42 Answer.
bro there is a way to get rotation right pls tell me
 
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the funny thing is this question is 3 marks .. so not sure what the answer will be .. lool

I would say the answer is 6. double of the radius .. the least possible value will be when it is exactly the width of the circle.
But the actual answer is 4.. :)
 
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But the actual answer is 4.. :)


Ah .. my bad .. I thought we had to take out the whole circle ...

check this picture the line in green is what we need to find out .. and then add it to 3.

ygyC


from the part above it we know that the reflex angle was 210 .. so the other angle will be 150 degrees..

we need to find the shortest difference .. and that difference in the perpendicular distance between two lines... so that line will bisect the 150 degree angle and make a right angled triangle ..

and we have two 75 degree angles ..

75 degree angle .. one side is 3 m (hypotenuse) .. i guess you know the trignometry rules :p

yes it is, but how did u do it??


well i don't know what the official method to this question is .. but what I did was simple direct proportion ..

it drops 4 meters in 200 seconds ..
how many meters will it drop in 150 seconds?
cross multiple 4*150/200 .. the answer came 3 .. which i subtracted from 8.. answer 5.
 
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[URL='http://www.xtremepapers.com/papers/CIE/Cambridge%20International%20O%20Level/Mathematics%20D%20(Calculator%20Version)%20(4024)/4024_s09_qp_2.pdf' said:
http://www.xtremepapers.com/papers/...(Calculator Version) (4024)/4024_s09_qp_2.pdf[/URL]
(5)(a)(i)(c),(a)(ii), (7)(b)(iii), (8)(a)(ii), (11)(b)(iii)(b).
with method please.. :) Thank u.. ;)

a ii ) calculate distance of ALi (area under the graph) = 0.5 ( 5 + 8 ) x 150 = 975m
if Ben is runnin at constant speed then his figure should be like a rectangle becox his speed would be straight line and length will be 150 as we have to calculate for 150 seconds thus
975 = 150 x w
w= 6.5 m/s bens speed

7 b (iii) u calculated area of triangle AOB
like 0.5 x 9 x 9 x sin 140 = 26.03 cm2
height of triangle will be 0.5AB/tan 70
then area of triangle will be 0.5 x b x h
0.5 x 0.5AB/tan70 x AB = 26.03
AB = 16.9cm (tell me if its correct)

8 a ii
BC x X = 168
BC = 168/x :S

11 b (iii) bus tumhe (8,2) per enlargement apply karni hai centre of enlargement or scale fctor tum ne previous parts mein nikal lia hoga
 
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