What is the value of the integer n?
(1) n(n+2)=15
(2) (n+2)^n =125
How will i know the sufficient statement?
OA B
(1) n(n+2)=15
(2) (n+2)^n =125
How will i know the sufficient statement?
OA B
Hello.
I would solve this as follows:
(1) n(n+2)=15.
This is not sufficient because this contidition implies that n=3 or n=-5, because $$3\left(3+2\right)=3\cdot5=15$$ $$-5\left(-5+2\right)=-5\cdot\left(-3\right)=15$$ Hence, this statement is not sufficient to determine the value of n. INSUFFICIENT.
(2) (n+2)^n = 125.
Now if we rewrite this expression we get that $$125=125^1\ \ \ \ \ \ or\ \ \ \ \ \ \ \ 125=5^3=\left(3+2\right)^3.$$ Hence, we get from this that n=3. Therefore, this statement is SUFFICIENT.
Thus the answer is the option B.
