Another maths question

Why cube root? You've got 4 years of growth there not 3

(810/620)^(1/4)
- 1
*100
=6.9%

actually... i was assuming end year 1 to end year 5... (so 4 years)... you probably mean start year 1 to end year 5, in which case change the 1/4 to a 1/5

Sorry I meant quadruple root.

JLivermore, that's the right answer (6.9%) but what does the ^ symbol mean? (and more importantly how do I do it on my calculator.

Many thanks indeed - betfair forum has become the place to go for maths help!

^ to means to the power, ie squared (^2), cubed (^3), ^1/4 is what you're referring to when you say quadruple root. 

There should be a button on your calculator y(root sign)x

Thanks a lot, I've just been using my calculator wrong..... I can do it now. I think I was doing square root and times by 4, thinking I was doing quadruple root.

Thank you very much indeed both of you, very helpful.