I dont know where this question goes If it is in wrong section please put it in correct, Next time i will not do mistake

well so the question is

Find the first four central moments for following

Its ungrouped data

1)4,3,6,5

and the book also gives the answers

that μ1(a)=0.5 , μ2(a)=1.5 , μ3(a)=-2 and μ4(a)= 4.5

I get these values correct by the formula

μ1(a)=mean-assumed mean

μ2(a)=μ2-μ1(a)^2

I took the assumed mean 5 by calculating 4+3+6+5/4

But now i have to find central moments

i.e.

μ1,μ2,μ3,μ4

I have found answers of

μ1=0

μ2=1.25

But i am not getting the following answers Which the book is given

μ3=0

and

μ4=2.56

else i get some big values can anybody help me please