# A simple question

1. ### hpla

11
hey >>>

i want to Calculate this area Equation :

A= pi *(D^2*d^2)*p*n*k

n= 0.5
k=0.4

but the Valuable of ( D-d-p) given like this :

D:d:p
4 1 4

My question is :

i dont understand Valuable of ( D-d-p)

is it Number or proportion ... just can any one make it clear to me

2. ### SteamKing

9,579
Staff Emeritus
It looks like a series proportion to me. D and p are each 4 times the value of d.

3. ### hpla

11
Thank you for your response .. u mean

D= 4d P=4d

4. ### SteamKing

9,579
Staff Emeritus
Yes.