SOLUTION: P is inversely proportional to d^2 P = 10,000 when d = 0.4 Find the value of P when d = 0.8 I know that P = k/ d^2 so .. k/ 0.64 = 10,000 but i dont know how to use the n

Algebra ->  Proportions  -> Lessons -> SOLUTION: P is inversely proportional to d^2 P = 10,000 when d = 0.4 Find the value of P when d = 0.8 I know that P = k/ d^2 so .. k/ 0.64 = 10,000 but i dont know how to use the n      Log On


   

Question 567594: P is inversely proportional to d^2
P = 10,000 when d = 0.4
Find the value of P when d = 0.8
I know that P = k/ d^2
so .. k/ 0.64 = 10,000
but i dont know how to use the numbers given to find the value
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
P is inversely proportional to d%5E2.
P+=+k%2Fd%5E2 Given that P+=+10000 when d+=+o.4 make the substitutions:
10000+=+k%2F%280.4%29%5E2 Solve for k:
k+=+10000%280.16%29
k+=+1600 so...
P+=+1600%2Fd%5E2 now substitute d+=+0.8
P+=+1600%2F%280.8%29%5E2 Evaluate.
P+=+1600%2F0.64
P+=+2500