Quartiles divide a dataset into 4 groups. The first quartile is the 25th percentile and has 25% of the values below it. The seond quartile, on the other hand, is the median or the 50th percentile with 50% of values below it; meanwhile, the third quartile has 75% of values below it.
Since we know that 138 lbs is the second quartile, then we can say that it is the median of the dataset. Therefore, there will be 50% of the sutdents who will weigh more than 138 lbs.
