###Human: Mr. Roper cuts his lawn 15 days a month beginning in April and ending in September.  From October to the end of March he cuts his lawn three times a month.  What is the average number of times that Mr. Roper cuts his yard per month?, ### Assistant: For 6 months of the year he cuts his yard 15 days per month so he cuts his yard 6*15 = 90 times
For the remaining 6 months of the year, he cuts his yard three times a month so he cuts his yard 6*3 = 18 times
He cuts his yard 90 times for part of the year and 18 times for the rest of the year for a total of 90+18 = 108 times
There are 12 months in a year and he cuts his yard 108 times so he averages 108/12 = 9 times per month 
 So the answer is :  9