Given, \( \Large r_{1} \) = 20% and \( \Large r_{2} \) = 20%

Therefore, Single discount equal to \( \Large r_{1} \) and \( \Large r_{2} \)

= \( \Large \left(r_{1}+r_{2}-\frac{r_{1} \times r_{2}}{100}\right) \)%

= \( \Large 20+20-\frac{20 \times 20}{100} \) = 40 - 4 = 36%