easymath

If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?

5 minutes. Each machine makes a widget at a rate of 1 widget every 5 minutes.

Why this works

This riddle cleverly plays with the relationship between machines, time, and output. Each of the 5 machines produces 1 widget in 5 minutes, so regardless of the number of machines, they all operate at the same rate. Therefore, if you have 100 machines working simultaneously, they can still produce 100 widgets in the same 5 minutes, since they are all working at the same pace as the original 5 machines. It's a fun way to highlight that increasing the number of machines doesn't change the time it takes to make the widgets, as long as they are all working together!

Common Wrong Answers

“100 minutes”

This answer assumes that all 100 machines work sequentially rather than simultaneously. Since each machine operates independently, they can produce widgets in parallel.

“1 minute”

This guess implies that the machines can produce widgets much faster than they actually can. The rate established by the riddle is that it takes 5 minutes for any machine to make a widget.

“25 minutes”

This answer incorrectly assumes that the time taken increases with the number of machines. In reality, the time remains constant because each machine is still producing at the same rate.

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