Try the following ACT math practice question that tests your understanding of logarithmic operations.
If $3 = k\cdot 2^r$ and $15 = k\cdot 4^r$, then $r =$
- $\quad -\log_{2}5$
- $\quad \log_{5}2$
- $\quad \log_{10}5$
- $\quad \log_{2}5$
- $\quad \dfrac{5}{2}$