# Thread: Series - I'm rubbish at series!

1. ## Series - I'm rubbish at series!

Hi everyone,

This is my first post..

Water fills a tank at a rate of 150 litres during the first hour, 350 litres during the second hour, 550 during the third hour and so on. Find the number of hours necessary to fill a rectangular tank 16m x 9m x 9m.

Anythoughts would be much appreciated!!

Thanks

2. ## Re: Series - I'm rubbish at series!

3(50) , 7(50) , 11(50) , ... , (4n-1)(50) , ...