opinion from Hapsah, et al. (2017), which stated that 
the incorrect problem understanding will lead to 
incorrect representation. Errors in understanding the 
problem also cause the modelling process from one 
representation into other representation to be 
incorrect (Murniasih, 2016). After understanding the 
problem, the right strategy is needed to solve the 
problem (Risalah, et al., 2016).  
The researchers conducted an interview with the 
pre-service teachers who made errors in doing the 
representation translation in number sense problems. 
The interview was not conducted on all of the pre-
service teachers, but it was classified based on the 
characteristics of errors from the answers. From 
each group, one person was chosen to be 
interviewed. 3 subjects was chosen for the interview, 
namely X1, X2, and X5. A break was given in every 
interview so that the subjects could give the 
complete answer. This is in line with the opinion 
from Juairiyah et al. (2014). Based on the interview 
with subject X1 on the first problem, subject X1 was 
able to translate the decimal representation into 
fraction representation, but he found difficulties in 
finding the final answer. Subject X1 was confused 
because the addition was infinite, so he could not 
write down the final answer. Subject X1 stated that 
the denominators were distinct, thus he did not know 
how to add them. On the second problem, subject 
X1 stated that he was confused because the area was 
unknown; therefore, he could not find the final 
answer. Based on the interview with X2, on the first 
problem, subject X2 did not know the procedure; 
therefore, he directly gave the incorrect final answer. 
On the second problem, subject X2 stated that the 
area was unknown, so he could not find the final 
answer. Based on the interview with X5, on the first 
problem, subject X5 could not solve the problem 
because he forgot the steps. The researchers asked 
whether he had done similar problem before, and he 
answered that he had, but he could not recall the 
steps at all. On the second problem, subject X5 
stated that he had difficulties with fractions. Based 
on the interviews, we can see that the learning for 
the pre-service teachers is still not effective. 
Ineffective learning is the cause of the students’ 
inability to solve non-routine problems (Whittle and 
Pacaya, 2007; Heath, 2010; Wright, 2016).  
4 CONCLUSIONS 
Based on the result and discussion, the 
representation translation in number sense is still a 
problem for the pre-service math teachers. The pre-
service math teachers made more mistakes in 
translating the decimal symbols representation into 
written language representation and fraction symbols 
representation. On the other hand, they made less 
mistakes in translating the pictures representation 
into written language representation, fraction 
symbols representation and decimal symbols 
representation. Further research are recommended to 
study about the obstacles in representation.   
ACKNOWLEDGEMENTS 
We would like to express our gratitude to all parties 
who had helped us in completing this article: 
Universitas Kanjuruhan which sponsored us 
financially; Prof. Dr. Cholis Sa’dijah, M.Pd, M.A. as 
advisor I; Dr. Makbul Muksar, S.Pd., M.Si. as 
advisor II; Dr. Susiswo, M.Si. as advisor III; and 
State University of Malang for providing us with a 
comfortable place to study and learn. 
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