A livestock company reports that the mean weight of a group of young steers is 10881088 pounds with a standard deviation of 7373 pounds. Based on the model ​N(10881088​,7373​) for the weights of​ steers, what percent of steers weigh ​a) over 10001000 ​pounds? ​b) under 12001200 ​pounds? ​c) between 900900 and 10501050 ​pounds?

Respuesta :

Answer:

a) 88.60%

b) 93.75%

c) 29.63%

Explanation:

We normalize to convert into a P-z value:

[tex]\frac{X - \mu }{\sigma} = P_z\\[/tex]

Where:

X is the given data we want to conver

mu is the mean

and sigma the deviation.

(1,000 - 1,088)/73 = -1,20547945

P(-1.20) = 0.114009133

11.40% is below 1000 pounds, we are asked for above thus:

100% - 11.40% = 88.60%

(1200 - 1,088)/73 = 1,534246575

P(1.534246575) = 0.937515498

93.75% of the livestock will weight below 1200 pounds

(900 - 1000)/ 73  = -1,369863

P(-1.369863.) = 0.005007044

0.5% weights below 900 pounds

(1050 - 1000) / 73 = 0,6849315

P(0.6849315) = 0.30134086

30.13% weight below 1050 pounds

we subtract the 900 livestock to get our answer:

30.13 - 0.5 = 29.63%

Wth the Pz values we get the probabiliies