Question Number 191071 by cortano12 last updated on 17/Apr/23

$$\:\:\underbrace{\boldsymbol{{R}}} \\ $$
Commented by cortano12 last updated on 17/Apr/23

Commented by horsebrand11 last updated on 18/Apr/23

$$\:{shaded}\:{area}\:=\:\mathrm{135}−\mathrm{41}.\mathrm{5}−\mathrm{18}−\mathrm{18} \\ $$$$\:=\:\mathrm{58}.\mathrm{5}\: \\ $$