$$\frac{3}{4}+\frac{3}{10}-\frac{50}{100}\$$  

$$\frac{3}{4}+\frac{3}{10}-\frac{50}{10}\$$  

$$\frac{3}{4}+\frac{3}{100}-\frac{50}{100}\$$  

$$\frac{3}{4}+\frac{0,3}{10}-\frac{50}{100}\$$  

$$\frac{6}{14}$$  

$$\frac{42}{40}$$  

$$\frac{6}{40}$$  

$$\frac{30}{40}$$  

$$\frac{11}{20}$$  

$$\frac{13}{20}$$  

$$\frac{9}{20}$$  

$$\frac{17}{20}$$  

$$\frac{6}{14}$$  

$$\frac{42}{40}$$  

$$\frac{6}{40}$$  

$$\frac{30}{40}$$