A 14.4 kg gas cylinder runs for 104 hours when smaller burner on gas stove is fully opened while it runs for 80 hours when larger burner on gas stove is fully opened. Which of se value is closest to percentage difference in usage of gas per hour, of smaller burner over larger burner ?

Consumption of gas in the smaller burner in 1 hour :
$$\eqalign{ & = \left( {\frac{{14.4}}{{104}}} \right){\text{kg}} \cr & = \frac{9}{{65}}{\text{kg}} \cr} $$
Consumption of gas in the larger burner in 1 hour :
$$\eqalign{ & = \left( {\frac{{14.4}}{{80}}} \right){\text{kg}} \cr & = \frac{9}{{50}}{\text{kg}} \cr} $$
Difference in consumption :
$$\eqalign{ & = \left( {\frac{9}{{50}} - \frac{9}{{65}}} \right){\text{kg}} \cr & = \frac{{27}}{{650}}{\text{kg}} \cr} $$
Required percentage difference :
$$\eqalign{ & {\text{ = }}\left( {\frac{{27}}{{650}} \times \frac{{50}}{9} \times 100} \right)\% \cr & = \left( {\frac{{300}}{{13}}} \right)\% \cr & = 23.07\% \cr} $$