Deon Tan's answer to Jon cheryl's Primary 3 Maths question.

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Deon Tan
Deon Tan's answer
2 answers (Tutor Details)
1st
Note that since packet 3 is lighter than packet 2, it also meant packet 2 is heavier than packet 3. Since that is the case, we can determine that packet 3 is the lightest.

Hope that the illustration brings you to the answer.