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What is the maximum number of bottles, each of diameter 8 cm, that can be packed
into a box with a square base measuring 632 cm by 632 cm?
(Using the hexagonal packaging pattern)
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Usual "square cells" paking scheme gives the answer = = 6241 bottles.
"Equilateral triangle cells" packing scheme has the distance (the shift) between the lines of centers of every two adjacent rows of bottles
h = = 6.9282 cm;
Hence, the number of such lines of centers is
= = = 90.06668399 (rounded to integer number 90).
It means that we have the sequence of numbers of bottles in paired rows as
(78 + 79) + (78 + 79) + . . . + (78 + 79). (1)
Each sum in parentheses in (1) is 78+79 = 157 bottles and the number of such groups of 157 bottles in (1) is 90/2 = 45.
Hence, the total number of bottles at such packing is 157*45 = 7065 bottles. ANSWER
For completeness, compare the two numbers for two packing schemes.
Solved.