IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => IGCSE/ GCSE => Math => Topic started by: Most UniQue™ on May 14, 2011, 07:43:05 am

Title: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 07:43:05 am
O/n 2008 q 6b (ii)

Pls help got exam on Monday plzzz help!!
Title: Re: Pls help as soon as possible
Post by: EMO123 on May 14, 2011, 10:02:59 am
O/n 2008 q 6b (ii)

Pls help got exam on Monday plzzz help!!
which paper and which board(as, a or Igcse)?
Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 12:25:03 pm
which paper and which board(as, a or Igcse)?

Oops sry p42 igcse
Title: Re: Pls help as soon as possible
Post by: Ghost Of Highbury on May 14, 2011, 12:31:02 pm
O/n 2008 q 6b (ii)

Pls help got exam on Monday plzzz help!!

find the standard width...the  height given = 11.5, its frequency is 115
therefore 11.5 = 115/n...=> n = 10
class width = 10 * standard width
2              =  10 * standard width
therefore standard width = 0.2
-----------------------------------------------------
now use this formula with standard width 0.2 to calculate the heights..
height = fequency * (standard width/classwidth)
1st - h = 35 * 0.2/10 = 0.7
2nd - 11.5 (given)
3rd - h = 26 * 0.2/2 = 2.6
4th - h = 24 * 0.2/6 = 0.8
Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 01:00:07 pm
find the standard width...the  height given = 11.5, its frequency is 115
therefore 11.5 = 115/n...=> n = 10
class width = 10 * standard width
2              =  10 * standard width
therefore standard width = 0.2
-----------------------------------------------------
now use this formula with standard width 0.2 to calculate the heights..
height = fequency * (standard width/classwidth)
1st - h = 35 * 0.2/10 = 0.7
2nd - 11.5 (given)
3rd - h = 26 * 0.2/2 = 2.6
4th - h = 24 * 0.2/6 = 0.8

Where did u get 2 frm ?
Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 07:25:36 pm
Plz answer its very important got exam on monday! plz i really appreciate it!
Title: Re: Pls help as soon as possible
Post by: SauD~ on May 14, 2011, 07:28:38 pm
Plz answer its very important got exam on monday! plz i really appreciate it!
Dude come on msn -.-
Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 07:32:30 pm
Dude come on msn -.-

cn u scan it to me, i wont be able!
Title: Re: Pls help as soon as possible
Post by: Ghost Of Highbury on May 14, 2011, 07:33:25 pm
Where did u get 2 frm ?

read the question again. the class width is 2 for 20-22

Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 07:43:55 pm
read the question again. the class width is 2 for 20-22



I dnt c any 2! and wt do u mean by class width??
Title: Re: Pls help as soon as possible
Post by: SauD~ on May 14, 2011, 07:56:44 pm
I dnt c any 2! and wt do u mean by class width??
its the numbers in between... For example: 20<x<=30  class width is 10
                                                          23<x<=29 class width is 6

Length in a histogram is found by this formula:
Frequency density= Frequency/ class width

so

as you will see that 11.5 is found by 115/2 x 5
now do the same process including that >>>> x 5
you will receive the answer ^_^
Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 08:00:49 pm
its the numbers in between... For example: 20<x<=30  class width is 10
                                                          23<x<=29 class width is 6

Length in a histogram is found by this formula:
Frequency density= Frequency/ class width

so

as you will see that 11.5 is found by 115/2 x 5
now do the same process including that >>>> x 5
you will receive the answer ^_^

i got everything exce[t x 5? why x 5?
Title: Re: Pls help as soon as possible
Post by: Ghost Of Highbury on May 14, 2011, 08:04:44 pm
Again, read the question

"On a histogram, the height of the column for the 20<m<=22 interval is 11.5 cm."


The class is - 20<m<=22

The class width = 2


Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 08:08:13 pm
Again, read the question

"On a histogram, the height of the column for the 20<m<=22 interval is 11.5 cm."


The class is - 20<m<=22

The class width = 2




hmm got it Thanks a lot n saud Thanks a lot and plz answer the question which i asked... Thanks
Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 08:10:43 pm
oh saud i got it, u mean if v multiply 2 by 5=10 and 115 divided by 100, its 11.5 so dats y v use 5 , right?
Title: Re: Pls help as soon as possible
Post by: SauD~ on May 14, 2011, 08:14:39 pm
i got everything exce[t x 5? why x 5?
we have different class widths of diff sets of values :)
So the 11.5 is done by multiplying it with 5, to make it a common.. .
got it?
to make something in common in class width they multiplied it with 5
otherwise it should have been 115/2 = 57.5 cm

to make common in class width :)
Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 14, 2011, 09:47:50 pm
we have different class widths of diff sets of values :)
So the 11.5 is done by multiplying it with 5, to make it a common.. .
got it?
to make something in common in class width they multiplied it with 5
otherwise it should have been 115/2 = 57.5 cm

to make common in class width :)


No :( u mean in order to make it 11.5 u multiply it by 5?
Title: Re: Pls help as soon as possible
Post by: SauD~ on May 15, 2011, 10:58:06 am
No :( u mean in order to make it 11.5 u multiply it by 5?
DUde.
To find the length for 115 frequency thing,

Length is found by frequency density formula... so f.d. = frquency/class width
                                                                                  115/2 = 57.5  but they said it is 11.5
                                                        if we do like this   115/2 x 5  that will give 11.5
so they multiplied it with 5   
Title: Re: Pls help as soon as possible
Post by: Most UniQue™ on May 15, 2011, 11:10:22 am
DUde.
To find the length for 115 frequency thing,

Length is found by frequency density formula... so f.d. = frquency/class width
                                                                                  115/2 = 57.5  but they said it is 11.5
                                                        if we do like this   115/2 x 5  that will give 11.5
so they multiplied it with 5   


Yah I already got it Thanks