Mr Goh bought 10 kg of sugar and used 1.2 kg.<br><br>
&bull; Sugar not used = 10 − 1.2 = 8.8 kg<br>
&bull; Percentage not used = \(\frac{8.8}{10} \times 100\%\)<br>
&bull; = 0.88 × 100% = 88%<br>
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Final Answer: 88%