P(R_1R_2\ ou\ J_1J_2)=P(R_1R_2)+P(J_1J_2) \\\\P(R_1R_2\ ou\ J_1J_2)=P(R_1)\times P_{R_1}(R_2)+P(J_1)\times P_{J_1}(J_2)\\\\P(R_1R_2\ ou\ J_1J_2)=\dfrac{3}{6}\times\dfrac{2}{5}+\dfrac{2}{6}\times\dfrac{1}{5}\\\\P(R_1R_2\ ou\ J_1J_2)=\dfrac{6}{30}+\dfrac{2}{30}\\\\P(R_1R_2\ ou\ J_1J_2)=\dfrac{8}{30}\\\\P(R_1R_2\ ou\ J_1J_2)=\dfrac{4}{15}