Audrey likes to double the amount of key lime juice called for in the recipe, so she needs 1/4 cup x 2 = 1/2 cup of key lime juice.
There are 16 tablespoons in 1 cup, so 1/2 cup is equal to 16 tablespoons x 1/2 = 8 tablespoons.
Each key lime yields 1 tablespoon of juice, so Audrey needs 8 key limes.
#### 8
The answer is: 8
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
Audrey's key lime pie calls for 1/4 cup of key lime juice but she likes to double this amount to make it extra tart.  Each key lime yields 1 tablespoon of juice.  There are 16 tablespoons in 1 cup.  How many key limes does Audrey need?

### Answer:
