Answer:
Step-by-step explanation:
Let x = number of books that Hannah donated
We know that the number of students is 150 and the total number of books is represented by b, we can write that as:
Average number of books donated by each student = 
Now we know that Hannah donated 3 times as much as the average. We can write that as:
An operational definition can both define and measure the hypothetical construct. The hypothetical construct is also called psychological construct is an explanatory variable which cannot be directly observed. It is also a tool to understand someone’s behavior. For example measuring you friend happiness.
Area of a circle is pi x r ^2
R = diameter/2
R = 1.8/2 = 0.9
Area = 3.142 x 0.9^2
Area = 2.5 square cm.
