Low Yi Yin's answer to KENNY PHUA's Primary 4 Maths Singapore question.

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Low Yi Yin
Low Yi Yin's answer
251 answers (Tutor Details)
1st
There are 4 criteria for the number.Always start from the criteria that gives you the smallest set of numbers (in this case factors of 84) and then use the other criteria to narrow down.
Hope this helps! ;))