Explanation

This question compares an actual scenario with a hypothetical one. Start by figuring out the rate (speed) for Brenda’s actual walk. Since she walked 12 miles in 3 hours, she walked at a rate of 12 ÷ 3 = 4 miles per hour.

Now, in the hypothetical situation, she would walk the loop two more times, for a total additional distance of 12 × 2 = 24 miles. Her hypothetical speed would be half of 4 miles per hour, or 2 miles per hour.

Walking 24 miles at a rate of 2 miles per hour would take Brenda 24 ÷ 2 = 12 hours.

Alternatively, note that both of the changes—doubling the distance and halving the rate—have the same effect: Each change makes the trip take twice as long as it would have before. So the time required for this hypothetical situation is multiplied by four: 3 × 4 = 12 hours.

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