Question

If a is an integer, which of the 

Answer 1

So to work this out we need to find the 4th root of each of those and pick the one that gives an integer.

A: $\sqrt[4]{1.6*10^1^1} = 632.455...$ This is a decimal therefore not an integer.

B: $\sqrt[4]{1.6*10^1^2} =1124.682...$ Again a decimal, therefore not an integer.

C: $\sqrt[4]{1.6*10^1^3} =2000$ This is a whole number, so it is an integer.

D: $\sqrt[4]{1.6*10^1^4} =3556.558...$ Decimal, therefore not an integer

E: $\sqrt[4]{1.6*10^1^5} =6324.555...$ Again a decimal, not an integer.

The only one that gives an integer when put to the 4th root is C, therefore:

$1.6*10^1^3$ could be A^4, as the 4th root of it is an integer.