You are working for the meteorological department in Hawaii. Your job is to track the amount of rainfall received on 50 sites across Hawaii through the year. This type of statistical study is AN OBSERVATION
Since they are similar, and a side of 10 = a side of 4, the ratio would be 2.5 : 1. You would do 6 * 2.5, which would equal 15, and (15 + 2) / 2 = 8.5 or 17/2