Answer :
The crime rate decreased by a factor of 0.2
Given data:
The number of crimes that occurred in a city per 1000 people decreased from 46.7 in 1920 to 46.5 in 1930.
To calculate the decrease in the crime rate, we can subtract the crime rate in 1930 from the crime rate in 1920:
On simplifying the equation:
46.7 - 46.5 = 0.2
Hence, the crime rate decreased by 0.2 crimes per 1000 people from 1920 to 1930.
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