Ordinary least square regression analysis was used in order to measure the correlation of using practice tool and higher final exam grades Final grade was a dependent variable, these are independent variables which have been used:

Hours of Using the Practice Tool - duration of practicing the question was recorded and total number of hours spent on a practice tool.

Hours of Studying the E-book - timer was used to record the time spent on reading the E-book.

Speed. - "the number of points earned per hour of working on problem sets."

Earliness - "To get a measure of general study habits, we evaluate students’ tendency to procrastinate, or rather its inverse, their earliness in working on problem sets."