The problem asks to find the unit price for one bottle of natural spring water when a case of 24 bottles costs $10.20. To solve this:

1. Total price of case: $10.20
2. Number of bottles: 24

The unit price per bottle can be found by dividing the total price by the number of bottles:

$\text{Unit price} = \frac{10.20}{24} = 0.425$

Rounding to the nearest cent, the price per bottle is $0.43.

Would you like more details on this calculation or have any questions?

Here are some related questions:

1. What would the unit price be for a case of 36 bottles if the price remains proportional?
2. How does rounding affect the accuracy of unit price calculations in real-world transactions?
3. What is the total price for 10 bottles based on the calculated unit price?
4. If the store offered a 10% discount on the case price, what would the new unit price be?
5. How many bottles could you buy with $5.00 based on this unit price?

Tip: When dividing costs by quantities, always ensure you're using the correct units (like bottles or cases) to avoid errors.