Twelve million people at six cans a week is 3.744 billion cans a year, which over the 525,600 minutes a calendar year offers is 7,123 cans a minute, or 3.56 production lines, or 4.19 once 85 percent uptime is allowed. Size the same demand on a 40-hour week and you get exactly 15 lines, because the two calendars differ by 219/52 = 4.2115, a systematic factor that no numerator guess can cancel. Sweeping all four inputs over 200,000 draws moves the count between 1.4 and 7.7 with a median of 3.4, so the conclusion is sturdier than any of the guesses inside it.
The reflex answer is that nothing can be weighed without a scale, and it is wrong: an aircraft resting on inflated tyres is already standing on four scales, each with a dial on it. Pressure times contact patch gives 160,000 pounds, but the deliverable is the interval from 115,200 to 211,200 together with the direction of the bias. A stiff sidewall carries part of the load, so the reading is a floor rather than a measurement.
With no air, v squared equals 2gD gives 89.4 metres per second and t equals root of 2D/g gives 8.94 seconds, both stable under g = 10 or g = 9.81. Dividing the height by the impact speed returns 4.47 seconds, wrong by exactly a factor of two at every drop height, because a body released from rest averages half its final speed. Real air reverses the picture: a coin-sized disc reaches terminal velocity near 11.9 metres per second and takes about 34.6 seconds, so nine seconds is a floor and 200 miles an hour a ceiling.