Duplication times vary depending on the microorganism in question.
Explanation:
Bacterial growth is the division of a bacterium into two daughter cells in a process called binary fission. Assuming that no case of mutation occurs, the resulting daughter cells will be genetically identical to the original cell. In this way the duplication of the bacterial population takes place. The bacterial population experiences exponential growth.
Using the mass/volume percentage method for percentages of the solution, you simply divide the grams of solute by the volume of the solution and multiply by 100 to get your percentage. (75.0g/250mL)•100 = 30.0% solute