The problem asks us to compare two lengths: 6 miles and 31,678 feet, and determine which is greater.

1. Problem Description

The problem asks us to compare two lengths: 6 miles and 31,678 feet, and determine which is greater.

2. Solution Steps

To compare the two lengths, we need to convert them to the same units. Let's convert miles to feet.

We know that 1 mile = 5280 feet.

Therefore, 6 miles is equal to $6 \times 5280$ feet.

$6 \times 5280 = 31680$ feet.

Now we can compare 31,680 feet and 31,678 feet.

Since $31,680 > 31,678$, 6 miles is greater than 31,678 feet.

3. Final Answer

6 miles