What is the difference between the two verbal problems books?

For students in grades 3 – 6, we have The Hands-On Equations Introductory Verbal Problems Workbook. It contains some 80 verbal problems which can be solved using Level 1 of Hands-On Equations. For the middle school, we have The Hands-On Equations Verbal Problems Book which has more than 350 verbal problems covering all three levels of Hands-On Equations. Some of these problems will challenge your most advanced students!