Tzu En's answer to Help's Secondary 2 Maths Singapore question.

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Tzu En
Tzu En's answer
133 answers (Tutor Details)
1st
Masses are related to volume and are 3D, thus the units are usually cm³/m³
Surface area are 2D and their units are cm²/m².
To solve
You have to cube root ³√64/729
To find the ratio in length/height which is 4/9
Next to find ratio of surface area
(4/9)² = 16/81