Question 13

One-third of a milliliter is needed to provide 150,000 units.

To determine how many milliliters are required to provide 150,000 units from a solution containing 450,000 units per milliliter, we can set up a simple calculation. By dividing 150,000 by 450,000, we find that 1/3 of a milliliter will yield the desired amount.

A) 1/3

This option is correct because when we calculate the amount of solution needed, we divide 150,000 units by 450,000 units per milliliter. This results in 150,000 ÷ 450,000 = 1/3, meaning that 1/3 of a milliliter will contain the required 150,000 units.

B) 4/3

This option is incorrect as it suggests that more than one milliliter is needed. Since 4/3 milliliters equals approximately 1.33 milliliters, this amount would provide significantly more than the required 150,000 units, specifically 600,000 units.

C) 1/4

This option is also incorrect. One-quarter of a milliliter equals 112,500 units when calculated (450,000 × 1/4 = 112,500), which is insufficient to meet the requirement of 150,000 units.

D) 3/4

This option is incorrect as well. Three-quarters of a milliliter would yield 337,500 units (450,000 × 3/4 = 337,500), which exceeds the requirement of 150,000 units, indicating that more than necessary is being considered.

Conclusion

The calculation indicates that 1/3 of a milliliter is the precise volume needed to deliver 150,000 units of the antibiotic solution. All other options either understate or overstate the amount required, confirming that 1/3 is the only correct answer based on the given concentration of the solution.