The reduction of 20% in the price of rice enables a person to obtain…

We Know 20% = \(\frac{1}{5}\),

Consumption difference = 5 - 4 = 1 unit = 50 kg,

then, 4 unit = 4 x 50 = 200 kg,

So, Price of 200 kg is Rs. 450,

Therefore price of 1 kg = \(\frac{450}{200}\) = Rs. 2.25.