To determine the original price per kg of sugar, we start by considering the information given:
A person spends Rs. 240 and with a 20% reduction in price, they can buy 6 kg more sugar.
\(\frac{240}{0.8x} = \frac{240}{x} + 6\)
\(\frac{240x - 240 \times 0.8x}{0.8x \times x} = 6\)
\(\frac{48}{0.8x} = 6\)
The original price per kg of sugar is Rs. 10.