For the first one, the range is the largest number minus the smallest number. The largest number in this case is 11 and the smallest is 4. 11 - 4 = 7 so the maximum range is 7 inches.
For the second one, the IQR is Q3 - Q1. This means 30 - 20 = IQR and 30 - 20 is 10 books.
And the last one asks for dinner customers, and there are 54 total. 28 of them chose cheesecake as their favorite dessert. This means that the amount of dinner customers that chose cheesecake as their favorite is 28/54 or 0.5185, whihc is 51.85%
