Question

Score for a cricket match is 3,42,0,6,18,100,9,12,18,14 and 20.What is the avearge score?

Answer 1

add all of them and divide it by number of terms

Answer 2

Average is a bad word to use because it could be one of many things.
One of the averages is like ankur504 said, add all of them and divide by the number of terms. (mean)
Another is just taking the number that appears most often. (mode)
The last, common, way is to put them in order from least to greatest and take the middle number. (median)