Hi,
Can any one let me know that which MGMAT book contains the topic of arithmetic & geometric series?
Thanks in Advance!
trapanister Wrote:Hi.
Surfing on google about the argument of G.P. i find this kind of statement
If the ratio of the sum of the first 6 terms of a G.P. to the sum of the first 3 terms of the G.P. is 9, what is the
common ratio of the G.P?
To solve the problem is used this formula
ar^n-a/r-1
I think this is rare as question on gmat, however I didn't see it in the guide 3th.
I have to worry about ???
Thanks to the staff