$\frac{10}{100}\times300$  

 $\frac{100}{10}\times300$  

 $\frac{10}{300}\times100$  

 $\frac{100}{300}\times10$  

 $\frac{25}{400}\times100$  

 $\frac{400}{100}\times25$  

 $\frac{25}{100}\times400$  

 $\frac{100}{25}\times400$  

$\frac{12}{100}\times500$

$\frac{12}{500}\times100$

$\frac{100}{12}\times500$

$\frac{500}{100}\times12$

 $\frac{500}{50}\times100$  

 $\frac{500}{100}\times50$  

 $\frac{50}{500}\times100$  

 $\frac{50}{100}\times500$  

 $\frac{5}{100}\times250\$  

 $\frac{5}{250}\times100\$  

 $\frac{250}{100}\times5$  

 $\frac{5}{250}\times100\$  

 $\frac{20}{100}\times350$  

 $\frac{100}{20}\times350$  

 $\frac{20}{350}\times100$  

 $\frac{350}{100}\times20$  

 $\frac{100}{45}\times480$  

 $\frac{45}{480}\times100$  

 $\frac{45}{100}\times480$  

 $\frac{480}{100}\times45$  

$\frac{99}{1500}\times100$

$\frac{99}{100}\times1500$

$\frac{100}{1500}\times99$

$\frac{1500}{100}\times99$

 $\frac{x}{500}\times100$  

 $\frac{x}{100}\times500$  

 $\frac{500}{100}\times x$  

 $\frac{100}{x}\times500$