Question

3. with three children, what is the expected number of girls? (Exclude multiple births and each sex is equally likely at each birth.) 4. What is the expected value of the roulette game? Assume roulette wheel slots are numbered 00, 0, 1, 2, 3, . .., 36; that the bet is on a single number and that the game pays $35 to $1. 5. A box of 18 flash drives contains 4 defective drives. You purchase a group of 3 drives randomly selected from that box. What is the expected number of defective drives in your 3-drive group? 6. A pair of fair dice is rolled once. What is the expected value of the sum showing on the two dice?

Answer 1

3) No af girs Total no af children PE prob af Let 3 एर्ि Bin In- 3 P 05) child Here X na ot girls Expected 3 x0.5 1.5 case of hypergeometric dishibution This is a cohich descri be prahability af Sulcesses n draus tinite populatian af size N that cantain without replacement froma exacly cbiccts with that featur

means purchasing deftchive Here Sucuess drive M= 4 DE3 N= 18 ECx) Mean - nM 34 18 O-6667 11 pair a dice is thrawn then samlt Speit is SL ,2), C,3) ,4)(1.5) (1.6) (2.5), (2,6) (3,2)(3.3) (3.4) (3. 5) (3.6) (4.4) (4.5) (4.6) (5,4) (5.5)(5.6) 6.4) (6.5) (6,6) (2,2) C2,3) 2,4 (3,1) (4,1) (4.3) (S.) (5,2) (S3) (6,1), (6.2)(6,3), (4,2) Pr caabiliy dishobuhan af Sum on tewa dict is 2 41 10 12 11 36 /36 346 4/36 5h 6 5/ac 1/366 6 36 PCX) 2XPIX) ELx) 2x1 + 3x2 36 2 XI 36 36

E(X)