# Moderate Algebra Solved QuestionAptitude Discussion

 Q. When the index of an exponential expression with a positive base is doubled, then the expression increases by $700%$. If one of the values that the base cannot have is $X$ which of the following is not a possible value of $P$?
 ✖ A. 4 ✖ B. 8 ✖ C. 5 ✔ D. 1

Solution:
Option(D) is correct

Let the expression be $a^n$

$\Rightarrow a^{2n}=8a^n$

$\Rightarrow n=\log_a8$

$a$ can be 5, 4 and 8 but it cannot be 1

## (1) Comment(s)

Ravi
()

Can somebody provide a simpler explanation