the mean is the average. so to get the mean, add up all of the numbers, and then divide by the number of numbers you added up. so in this case, you ad up -2+14+(-18)+(-6). once you have added them up, divide by four, because there are four numbers. that will give you the average. so, -26 (-2,-6,and -18) and 14. add these together to get 12. you added up four numbers, so now divide 12 by 4 to get 4. the average number of yards is 4. :)