2007 AMC 8 Problem 22

Below is the professionally curated solution for Problem 22 of the 2007 AMC 8, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2007 AMC 8 solutions, or check the answer key.

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Concepts:square (geometry)invariant

Difficulty rating: 1550

22.

A lemming sits at a corner of a square with side length 1010 meters. The lemming runs 6.26.2 meters along a diagonal toward the opposite corner. It stops, makes a 9090^{\circ} right turn and runs 22 more meters. A scientist measures the shortest distance between the lemming and each side of the square. What is the average of these four distances in meters?

22

4.54.5

55

6.26.2

77

Solution:

Based on the lengths given in the problem, the lemming is still in the square after it stops.

Since the lemming is still in the square, the sum of the distances to the horizontal sides is 1010 meters and the same for the vertical sides. Therefore, the 44 distances sum to 2020 meters, making the average 20÷4=520 \div 4 = 5 meters.

Thus, C is the correct answer.

Problem 22 in Other Years

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