11) (1 8/5 + 15) * 6

$$\left(1 \frac{8}{5} + 15\right) \cdot 6 = \left(\frac{13}{5} + 15\right) \cdot 6 = \left(\frac{13}{5} + \frac{75}{5}\right) \cdot 6 = \frac{88}{5} \cdot 6 = \frac{528}{5} = 105,6$$

Ответ: $$\bf{105,6}$$