Formative Assessment 93

Assessment Problem: 

Problem 2: One of the workers in the jam factory mixed one barrel of jam containing 14% of sugar with another barrel of jam containing 30% of sugar. The new
mixture weighs 80 kilograms and contains 20% of sugar. How much jam was in the first barrel? How much was in the second barrel?

Mathematical Issues: 

It is sometimes difficult to find problems that create true dilemmas for students. This series of problems creates the dilemmas through conversation with an interviewer as the learner interprets the problems in a verbal exchange.

Modeling & Word Problems
Conceptual understanding through word problems
Common Core Standards: 
7.EE: Expressions and Equations
7.RP: Ratios and Proportional Relationships
Research References: 
Cifarelli, V. (1991). Conceptual structures in mathematical problem solving. Paper presented at the annual meeting of the American Educational Research Association, Chicago, IL.