$$\frac{20}{40}:\frac{8}{26}=$$

$$\frac{20}{40}\times\frac{26}{8}=$$

$$\frac{\cancelto{1}{20}}{\cancelto{2}{40}}\times\frac{26}{8}=$$

$$\frac{1}{2}\times\frac{26}{8}=$$

$$\frac{2}{\cancelto{1}{2}}\times\frac{\cancelto{13}{26}}{8}=$$

$$\frac{13}{8}$$