In this study, transitional thinking was most frequent among the four kinds of multiplicative thinking levels. This means that many students still have a difficulty in distinguishing multiplicative situations from additive situations. Given that the transition from additive to multiplicative thinking is not as smooth or straightforward as most curriculum documents seem to imply (Siemon & Breed, 2006), this kind of thinking is likely to be an obstacle for students to learn subsequent topics such as ratio and proportion. In this respect, multiplicative thinking is needed to be developed by dealing with lots of multiplicative situations.