Problem 1. There are three acrobat brothers. Their average height is 1 meter 74 centimeters. The average height of two of these brothers: the tallest and the shortest - 1 meter 75 centimeters. What is the height of the middle brother? Justify your answer.
Answer: 1 meter 72 centimeters.

Solution. Since the average height of all three is 1 meter 74 centimeters, the total height of all three is 5 meters 22 centimeters. The average height of the two brothers is 1 meter 75 centimeters, so their combined height is 3 meters 50 centimeters. Therefore, the height of the middle brother is 1 meter 72 centimeters.

## Criteria

2 p. Correct solution approach, but an arithmetic error was made.

4 p. The correct answer and justification are provided.