It rained for a total of 3.79+4.5+3.95+3.09+4.67 = <<3.79+4.5+3.95+3.09+4.67=20>>20 inches
The rain period is from March through July for a total of 5 months so the average rainfall is 20/5 = <<20/5=4>>4 inches of rain per month
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