How many terms of the geometric series `1+4+16+64+` will make the sum `5461` ?

Explanation

Let the sum of n terms of the given series be 5461.

Therefore,

`S_n​=5461`

`=>(a(r^n−1​))/(r-1)=5461`

`=>(4^n−1)/(4-1)​=5461`

`=>4^n−1=16383`

`=>4^n=16384`

`=>4^n=4^7`

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