urgent help 4 maths paper 4

[godfather93]

can someone please explain this question to me? this question has got me completely spinning.

[Wahab09]

sure.. but which one?

[godfather93]

sorry forgot to put the question!!
Question 9

[twilight]

the percentage of the total area which is shaded = shaded area/total area of the figure  x 100

the fraction of the total shaded area = shaded area/total area of the figure

[Wahab09]

Yea thats a tricky one.. i dont think theyl bring somethin like that this year cuz its kinda old..

but for the first one.. its 1/4 * 100= 25% i think its straighforward..

and the rest ima need a pen and paper to get it goin  

and By the way.. wat was question 6? also weird.. very hard..

[godfather93]

but how did you get the shaded area?

[godfather93]

astar please help!

[twilight]

get the shaded area in terms of h .. then the total area in terms of h .. and divide .. the h will get canceled

for the first diagram =>    answer is     (0.5 x 1 x h) / (0.5 x 4 x h)   x 100  =   1/4 x 100 = 25%

for the second diagram =>      (0.5 x 1 x h) / (4 x h)   x 100  =  1/8 x 100 = 12.5%

got it?

[godfather93]

i totally get it. Thank you very much. I was using the same method as you showed above before but i was making a very stupid mistake. I took the area, especially, of the triangle as being 1/4*b*h insteas of 1/8*b*h.
Thank you once again! (+rep)

[twilight]

ur welcum

[astarmathsandphysics]

9a)25% since A=0.5base*height and the heights are the same.

b)12.5 since A=base *height for the paralellogram and 1/5base*height for the triangle

c)37.5 since if you cut the kite in half downwards the base is in the ratio 1:3 so shaded area is 75% of the triangle the half this

d)Divide the traezium into 3 triangles then ans=60%

[astarmathsandphysics]

bi)20/180*100%


ii)pi*1^2/pi*5^2*100%=4%

ii)(pi3^2-pi2^2)/pi3^2=5/9=55.6%

[godfather93]

thanks! I understand the question now. I was making a silly mistake.

[godfather93]

oh. I'm stuck again at the same question. I don't get how to calculate the shaded area of diagram 4. That is a bit tricky.

[Wahab09]

dude stop stressin urself out.. this paper was ages ago its unlikely a question like that will come up..
they like to put a lil sequences ques at the end lately and theres many topics that didnt come on p2 that MUST come on p4 so theres no room for silly questions like these