This shows that the data varies for 25 different numbers. That HALF of the data is between 25 numbers.
Part C: Using a box-and-whisker plot you can interpret the different values. Minimum is the first dot (10), connected to the first line (Q1 which is 17.5), connected by a box to the median (30), connected by a box to the third line (Q3 which is 42.5), connected to the last dot which is the maximum (50). And IQR is Q3-Q1, so 42.5-17.5 which is 25.
