Question

_u-IgNsikr7;8P3jH-WvUgVx-Up SERIALES COP S ection 7.3 Exercises Next 1 Previous 2 3 4 5 6 Question 1 of 6 (1.5 points) View problem in a pop-up 6.3 Section Exercise 9 - 14 (calc A sample of size 50 will be drawn from a population with mean 12 and standard deviation 8. Use the TI-84 calculator. Part 1 Find the probability that x will be more than 10. Round the answer to four decimal places. The probability that I will be more than 10 is 0.9616 Correct answer: 0.9615 Part 2 Find the 45th percentile of x. Round the answer to two decimal places. The 45th percentile is 0.14 Correct answer: 11.86 HEWLETT-PACKARD

so i attempted to do this question and as you can see, i got it wrong. Can you explain how these answers were found with steps, formulas, and work shown please?

Answer 1

Given : µ = 12 , σ = 8 , n = 50

Therefore , µ = 12 and σ = $\frac{\sigma }{\sqrt{n}}$ =
50 2о
= 1.131371

Part 1)

P( > 10 )

We can use TI-84 calculator . Press  2ND key ---> VARS key ---> Select Normalcdf() hit enter .

TEXAS INSTRUMENTS DSTR DRAW Hnormalpdf( 2normalcdf 3TinvNorm 4: invT 5: tPdf 6:tcdf 74X2Pdf STAT PLOT F1 TELSETF2 FORMAT F3 CALC F4 TABLE FS Yu WINDOW GRAPH TRACE zoOM

TI-84 Plus Silver Edition TEXAS INSTRUMENTS orMalcdi lower: 10 UPPER: 100000 :12 : 1.131371 Paste STAT PLOT F1 TBLSET F2 FORMAT F3 CALC F4 TABLE FS WINDOW Y GRAPH TRACE ZOOM

TI-84 Plus Silver Edition TEXAS INSTRUMENTS normalcdf (10,1 .9615 STAT PLOT F1 TBLSET F2 FORMAT F3 CALC F4 TABLE F5 WINDOW Y GRAPH TRACE ZOOM

Answer : 0.9615

Part 2)

Select invNorm()

TI-84 Plus Silver Edition TEXAS INSTRUMENTS invhorM area:0.45 : 12 g: 1.131371 Paste STAT PLOT F1 TBLSET F2 FORMAT F3 CALC F4 TABLE FS ZOOM TRACE GRAPH WINDOW

TI-84 Plus Silver Edition TEXAS INSTRUMENTS invNorm(0.45, 12 11.8578 STAT PLOT F1 TBLSET F2 FORMAT F3 CALC F4 TABLE FS GRAPH WINDOW TRACE Y ZOOM

Answer : 11.86