q1 mock

[Priyanshu Singh]

please tell ans for question 1 how is ansder 10,please epxlain?

[Hussain Khambati]

Since summation of all relative frequency is equal to 1, the summation of all relative frequencies from 1 to 9 can be written as: 1-r10(r10 is the relative frequency of the 10th variable)

therefore a given in the question,

1.02π=  2π−π∗(1-r10)

1.02 π=2 π- π+ π r10

1.02 π=  π+ πr10

1.02 π= π(1+r10)

1.02=1+r10

r10=0.02

since total frequency is 500, the 10th frequency is r10*500=0.02*500=10

[Priyanshu Singh]

i  understodo till r10 =0.02, then why did u do 0)2*500 for finding freuqency of 10?

[ABHAY NARENDRAN]

Frequency = Relative frequency * Sample Size

[Priyanshu Singh]

Ok, thanks. 

[Srinath Sai]

Hi,

Relative frequencies according to their proportion are only represented as angles in a pie chart. Then if the statistician has used a wrong formula in calculating the angle of slices for the 9 categories, then he obviously has found a wrong total of the relative frequencies for the 9 categories. 

So, how can we take this wrong total of 1.02π as the basis for deriving the frequency of the 10th category, as the answer so derived will also be wrong only? 

Please advise.

[Malabika Guha Mustafi]

Here instead of 2 Pi * rf the statistician took pi.r.f.

.There was no change in individual r.f.

So, 2pi- pi(sum of r.f) pi=1.02 pi

( This equation is wrong to compute 10th r.f but true for sum of 9 r.f).

sum of r.f = 2-1.02=0.98

[Srinath Sai]

Thank you!