Problem P. 3857. (January 2006)
P. 3857. Thomas is long-sighted. He is able to see clearly only those objects which are at least 1 m away. Find the power of the glasses through which he is able to read a book 25 cm away from his eyes.
Deadline expired on February 13, 2006.
116 students sent a solution. 3 points: 85 students. 0 point: 23 students. Unfair, not evaluated: 8 solutions.