Required Mathematical Intelligence

Chapter 28
There is a square box with a side length of 10 cm filled with spheres with a diameter of 1 cm.Do you know how many balls you can line up at most?How should they be arranged to accommodate the most?
[答案：如果按每排10个的方法排列，显然只能排10×10=100个。看起来似乎排列的很紧密，其实这种排列法并不是最理想的，因为相邻2排球的中间有很大的空隙。设法减少这些空隙，就能多放一些球。减少空隙的方法是：将相邻2行互相错开排列。虽然有4行各少了1个，但却多出一行，所以比10×10的排法能多出10-4=6个。]
(End of this chapter)