Maths, Addmaths and Statistics: Post your doubts here!

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

Good point, Hamid Ali! I perfectly agree. Trying on your own will further clarify your concepts. A ready-made solution is the most easy way out but not the most productive one!

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

Exactly!
Anyways, I am sure you'll be able do the question according to the vector method shown in the video that is also taught in schools. I found another method by splitting each of the vectors into its horizontal and vertical componenents and then solving it using the relative velocity formula that can only be applied to parallel vectors. Hence, I am posting below the solution to the first part of the question using my method which I find easier to solve relative velocity problems. Hope it helps.

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

Ingenious! The thought that they could be split never occurred to me!

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

Here is the solution to your question, abcde.
The picture below shows an equilateral triangle that you can make. It is an equilateral triangle because C is the centre of the triangle while substending equal lengths (radius) to the vertices of the triangle. CXE is equal to 30 degrees and so is CEX. 180-30-30=120=ECX= DCE

Another approach to this question is by extending the tangents D and E until they meet and this forms a quadrant.

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

Q3. http://www.xtremepapers.me/CIE/Cambridg ... _qp_11.pdf i knw its preety simple but i dont know unitary method and i cant do it plz give full explanation and tips to how to tackle them

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

a)1 revolution has 360°. Let us assume the total number of cars to be X. 40 out of the total 360 are 7 red cars. So 40/360*X=7
1/9*X=7
X=7*9=63cars
b) Circumference of a circle is equal to πd
so πd=28
d=28/π

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

Here is the solution to your question, abcde.
The picture below shows an equilateral triangle that you can make. It is an equilateral triangle because C is the centre of the triangle while substending equal lengths (radius) to the vertices of the triangle. CXE is equal to 30 degrees and so is CEX. 180-30-30=120=ECX= DCE

Another approach to this question is by extending the tangents D and E until they meet and this forms a quadrant.

I understand the equilateral triangle method. Can you please elaborate on the second approach. Thank you!

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

Please answer this one!

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

Other little q help http://www.xtremepapers.me/CIE/Cambridg ... _qp_11.pdf
Q5b, Q7 (1), Q8b till now and little more elaboration please

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

Please answer this one!

theek hai

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

merai halwai q ka koi reply karai plz

and in Q9 a mine is 5.6 but in scheme it is 6 ?? http://www.xtremepapers.me/CIE/Cambridg ... _qp_11.pdf

umm well it was about smallest widht so phir bhi it shud be 5 what u say ??

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

Other little q help http://www.xtremepapers.me/CIE/Cambridg ... _qp_11.pdf
Q5b, Q7 (1), Q8b till now and little more elaboration please

Here is the solution for 5 (b):

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

Other little q help http://www.xtremepapers.me/CIE/Cambridg ... _qp_11.pdf
Q5b, Q7 (1), Q8b till now and little more elaboration please

Q80 (b)

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

For question 7, you basically have to use trial and error.
The first statement is true. Note that the cube of any number greater than 1 is always greater than 1.
Statement 2 is also true.
Statement 3 is false. e.g. if n = 5 then (5-1)(5+3) = 4 x 8 = 32, which is even. Thus the statement is false.
I hope this helped.

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

Jazakallah pal
but i want to know in 8 b y we add ratios ?? and i have tried ryt now the same procedure to solve 8 a although i did it with multiplying method but not possible

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

merai halwai q ka koi reply karai plz

and in Q9 a mine is 5.6 but in scheme it is 6 ?? http://www.xtremepapers.me/CIE/Cambridg ... _qp_11.pdf

umm well it was about smallest widht so phir bhi it shud be 5 what u say ??

Read the question carefully. Find the smallest width of a box that can always hold 8 pencils side by side.
For this calculate the upper bound of the diameter of each pencil. It is 7.5 mm. So if the box is to always hold 8 pencils side by side, its smallest width will be = 7.5 x 8 = 60.0 mm = 6.00 cm.
Understand? Try reading it again please.

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

Jazakallah pal
but i want to know in 8 b y we add ratios ?? and i have tried ryt now the same procedure to solve 8 a although i did it with multiplying method but not possible

What's not possible?

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

For question 7, you basically have to use trial and error.
The first statement is true. Note that the cube of any number greater than 1 is always greater than 1.
Statement 2 is also true.
Statement 3 is false. e.g. if n = 5 then (5-1)(5+3) = 4 x 8 = 32, which is even. Thus the statement is false.
I hope this helped.

if in the first statement n = 1 ?? then how 1 > 1 ??

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

Jazakallah pal
but i want to know in 8 b y we add ratios ?? and i have tried ryt now the same procedure to solve 8 a although i did it with multiplying method but not possible

What's not possible?

i tried same method as u showed me for 8a to practice this method
probably 9----> 14+x
then 7 ---> ((14/9)+x)*7

then how u'll get x ??

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

what about Q11 http://www.xtremepapers.me/CIE/Cambridg ... _qp_11.pdf i faced same difficulty when i faced similar q in my mock what to write in it ??