500, based on eyeballing the number of big numbers (between 15 and 20, I took 20 to adjust for the small numbers) and eyeballing the average value of the big nu

500, based on eyeballing the number of big numbers (between 15 and 20, I took 20 to adjust for the small numbers) and eyeballing the average value of the big numbers (25, I took a number slightly lower than I estimated because I knew that the 20 was probably too high). Giving the estimate 20*25=500.