Question Number 62914 by Tawa1 last updated on 26/Jun/19
Answered by MJS last updated on 27/Jun/19
$$\mathrm{this}\:\mathrm{is}\:\mathrm{very}\:\mathrm{easy} \\ $$$${R}=\mathrm{15} \\ $$$${r}=\frac{\mathrm{15}}{\mathrm{3}}=\mathrm{5} \\ $$$$\mathrm{blue}={R}^{\mathrm{2}} \pi−\mathrm{7}{r}^{\mathrm{2}} \pi=\mathrm{50}\pi \\ $$
Commented by Tawa1 last updated on 27/Jun/19
$$\mathrm{God}\:\mathrm{bless}\:\mathrm{you}\:\mathrm{sir} \\ $$