One person baught some kg of suger for RS 80. If he would get 4 kg sugar more with that money, then the price of 1 kg sugar would be less by RS 1.Hence find the required quadratic equation.

Explanation

Let the person bought x kg of sugar in RS 80.
`:.` the rate of value of sugar `RS=(80)/(x)//kg`.
If he would get 4 kg sugar more, then the rate of value of sugar would be `RS(80)/(x+4)//kg`.
As per question, `(80)/(x)-(80)/(x+4)=1or,(80x+320-80x)/(x(x+4))=1`
or, `(320)/(x^(2)+4x)=1or,x^(2)+4x=320`
or, `x^(2)+4x-320=0`.
Hence the required quadratic equation is `x^(2)+4x-320=0`