Given the data 21,13,13,37,13,23,25,15 what is the outliner

An outlier is a number that is much higher or lower than the other numbers and stands out. Here we have three 13s so you know this is NOT an outlier. 15 is close to 13 and 21 is close to 23 and 25. The outlier is most likely 37 since it is much greater than these numbers. Hope this helps! 

37 is the outlier in this mathematical question