7 Monsoon Rains The summer monsoon rains bring 80 of India s rainfall and are essential for the country s agriculture Records going back more than a century show that the amount of monsoon rainfall varies from year to year according to a dis tribution that is approximately Normal with mean 852 millimeters mm and stan dard deviation 82 mm 3 Use the 68 95 99 7 rule to answer the following questions a Between what values do the monsoon rains fall in the middle 95 of all years b How small are the monsoon rains in the driest 2 5 of all years