What is erroneous worked example and how is it looks like in social arithmetic?

Erroneous worked example is a part of worked example with some part of the solution intentionally given wrong or incorrect. Through erroneous worked example, students are asked to learn from the example given, find errors, then correct it. This method is believed to help students avoiding mistakes in the future. One of the materials that considered to be difficult in grade VII is social arithmetic because it mostly given in the form of word problems and requires some initial concepts such as basic operation, percentage, currency, relevant equation, etc. Research studies have found that students often made mistakes in solving social arithmetic problems. Erroneous worked example might become an alternative to help students making less mistakes, but it is also very important to know how to design a good erroneous example in order to make it works well with students. This review study focused on erroneous worked example and types of errors occurred when students solving social arithmetic or word problems. Those types of error used to design an instructional example in social arithmetic field. If the design is good then erroneous worked example would help students to systemically evaluate their mistakes and improve their problem-solving skill.