✔ 最佳答案
(a)(i) 7x7 = 49(ii) C(7,1) x C(7,2) + C(7,2) x C(7,1) + C(7,3)= 329(iii) C(7,1) x C(7,3) + C(7,2) x C(7,2) + C(7,3) x C(7,1) = 931(b)(i) C(5,2) x C(3+6+8,1) = 10 x C(17,1) = 170(ii) C(8,1) x C(14,2) + C(8,2) x C(14,1) + C(8,3) x C(14,0) = 1176(iii) 3 x 5 x 6 + 3 x 5 x 8 + 3 x 6 x 8 + 5 x 6 x 8 = 594