Nuclear Free New Zealand

How do we know that there are approximately 48,000 paper cranes in the five cartons pictured below, beside Mr. Barney Richards?

[1] Weights of the five full cartons, as checked in Japan and written on the packing slips.

Box 1 = 4070 grams

Box 2 = 3800 grams

Box 3 = 3850 grams

Box 4 = 3860 grams

Box 5 = 3850 grams 

Total = 19430 grams 

[2] Minus box weight, including plastic bags and strapping = 1182 for each x 5 boxes = 5910 grams

19430 minus 5910 = 13520 grams of paper cranes

[3] 50 cranes were found to weigh 0.014 grams

13520 grams divided by 14 grams = 966 groups of 50 cranes

[4] With 50 cranes per 14 grams     966 x 50 = 48285 paper cranes total approximately