if the distribution of data is skewed to the left, the meanis less than the median, which is often less than the mode. If the distribution ofdata is skewed to the right, the mode is often less than the median, which is less than the mean.
if the distribution is normal Mean = Mode = Median,
If the distribution is left skewed, Mean < Median < Mode
If the distribution is right skewed,  Mode < Median < Mean