You believe your child read 120 books in a year? Each book averaging 160 pages?
You are aware a year has 365 days?
You are aware 120 goes into 365 3 times with 5 left over?
You aware you paid on a claim of reading 1 book every 3 days?
You are aware 2 and 1/3 books were read per week on average?
Perhaps you little genius could reinvest that $120 in getting his father a MATH lesson.