If X is a normal random variable with men6andard deviation 1.9, then find the va

Question

If X is a normal random variable with men6andard deviation 1.9, then find the value x such that PIZ x) is equal to 0.81, as shown below. (Nole: the diagram is not necessarily to scale. Choose the closest answer.) 6.2663 8.168 721715 10.071 Find the z value that corresponds to the 60th percentile (3 decimals). (Z is the standard normal) Number The area to the right of2-1.8 is 0.0187 CZ has the stardard Normal distribution ) True False The National Broomball League claims to have a balanced league, that is, for any given game each team has an equal chance of winning or losing with no ties. Assuming the claim is true, what is the approximate probability that a given team will lose more than 60 games out of the 100 played? 0.0097 0.4009 0.0179 0.0138 0.7839 A printed circuit board has 285 small holes, called joints" into which are inserted the thin leads or 'pins" emanating from electronic components soldered to the printed circuit board Assuming that the quality of the solder joint at any pin is independent of the qualit at am other pr a bno al mass function can be used o describe x the number of defective solder ts. The probability that a given so der jo t is detective s 01. What is th, standard devlat on of the number of defective solder s on a printed cr board? it Note: Your answer should have 4 decimal places

Explanation / Answer

1) for 81th percentile ; zscore =0.8779

hence corresponding score =mean+z*std deviation =6.5+0.8779*1.9=8.168

2)

60th percentile ; z =0.253

3)

false ;as area to right of z=1.8 is 0.0359

4)

here mean games loose =100*0.5 =50

std deviation=(np(1-p))1/2 =5

threfore P(X>60)=P(Z>2.1) =0.0179

5) std deviation=(np(1-p))1/2 =(285*0.01*(1-0.01))1/2 =1.6797

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.