C2 Geometric series help

Stuck here on the sufficient method to approach this question, would it involve using the a(1-r^n)/1-r formula? Any assistance would be greatly appreciated. Cheers.

'The sum of the first four terms of a geometric series is 5468.75 and the first term is 2000. Find the value of the common ratio and if all the terms are positive.'

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Originally Posted by DonGorgon

Stuck here on the sufficient method to approach this question, would it involve using the a(1-r^n)/1-r formula? Any assistance would be greatly appreciated.
'The sum of the first four terms of a geometric series is 5468.75 and the first term is 2000. Find the value of the common ratio and if all the terms are positive.'

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You have all the parts, use them.

2000r^4 - 5468.75r 3468.75 = 0

Along the right lines?