geometric series application question!!! (1 Viewer)

[anohana]

http://books.google.com.au/books?id... full and has a capacity of V litres"&f=false

In the answer, it used Tn=ar^n instead of Tn=ar^n-1
Why is that? Is it assuming the loss of water begins the second week? just want to doublecheck...

thanks

GOOD LUCK TO EVERYONE DOING THE EXAM TOMORROW

(I know the book is a bit outdated)

 

[UNCLE ROLFY]

http://books.google.com.au/books?id... full and has a capacity of V litres"&f=false

In the answer, it used Tn=ar^n instead of Tn=ar^n-1
Why is that? Is it assuming the loss of water begins the second week? just want to doublecheck...

thanks

GOOD LUCK TO EVERYONE DOING THE EXAM TOMORROW

(I know the book is a bit outdated)

what is the answer?

 

[anohana]

answer is n=ln(0.5) / ln(0.95) = 13.513
14th week