I think the mode is 9.875
21 hrs. Because if Harry worked one third the hrs thats Aiden worked then 7×3 =21 and 21÷3=7. So 7 is one third of 21.
A set whose elements belong to a given set : subset
a number that can be written as a ratio in faction form : rational number
a number in decimal form that does not terminate or repeat : irrational number
a number that can be written as an infinite decimal : real number
a collection or group of objects : set
a diagram that shows the relationship between sets : venn diagram
an object that belongs to the set : element
14 and 15
14^2 = 196
15^2 = 225
225+196 = 421