Question

Big babies: A government agency reports that

20%

of baby boys

6

-

8

months old in the United States weigh more than

27

pounds. A sample of

150

babies is studied. Use the $placeholder_icon.svg$ Cumulative Normal Distribution Table if needed. Round the answer to at least four decimal places.

(a) Approximate the probability that less than

39

babies weigh more than

27

pounds.(b) Approximate the probability that

37

or fewer weigh more than

27

pounds.

(c) Approximate the probability that the number who weigh more than

27

pounds is between

31

and

41

exclusive.

Part 1 of 3

The probability that less than 39 babies weigh more than 27 pounds is .

Part 2 of 3

The probability that 37 or fewer babies weigh more than 27 pounds is .

Part 3 of 3

The probability that the number who weigh more than 27 pounds is between 31 and 41 exclusive is .

Answer 1

27 lb 9. B= 20% = 0.2, 9=1-8=0.8, n = 150 M:n p=30, 65209=124 X! No of babies weigh more than , @ pix < 39). P(X<38.5) (continuity correction) = Plz 38:5-3°) - P(Z(1.74) = 0.959|| PlX537) = P(x< 37.5)= P(Z < 37.5-30)=Pz21053) = 0,9370 124 124 24 © P131<x<41) = P(39.5* <405)- D(31-5*30 <z«4019-30) - P(0.31< ZS 2014)- PIZ<2.14)-DIZ <0.31) = 0.9838-0.6217=0.3621