Question

each hour, the number of bacteria in dr. nalls petri dish tripled. what percent is the population compared to the population the hour before?
3%
30%
130%
300%

Explanation:

Step1: Define the relationship

Let the initial population be $x$. After one - hour, the population is $3x$.

Step2: Calculate the percentage

To find what percent the new population is of the old population, use the formula $\frac{\text{new population}}{\text{old population}}\times100\%$. Substitute the values: $\frac{3x}{x}\times100\%$. Since $\frac{3x}{x}=3$, then $3\times100\% = 300\%$.

Answer:

D. 300%