Question

If k is an integer and $\left(0.0025\right)\left(0.025\right)\left(0.00025\right)\times {10}^k$ is an integer, what is the least possible value of k ?

• A. -12
• B. -6
• C. 0
• D. 6
• E. 12

Answer 1

The correct option is E 12

Given expression:

$(25\times {10}^{-4})$ $(25\times {10}^{-3})$$(25\times {10}^{-5})$

$\to$ $15625\times {10}^{-12}$.

So, to make the result an integer, we must multiply by ${10}^{12}$

Least possible value of k should be 12. (option E)