Login

Welcome, Guest. Please login or register.

March 09, 2026, 07:25:43 pm

Author Topic: Probability help! (normal dist)  (Read 2566 times)  Share 

0 Members and 1 Guest are viewing this topic.

barydos

  • Victorian
  • Forum Obsessive
  • ***
  • Posts: 314
  • Respect: 0
  • School: Nossal High School
  • School Grad Year: 2013
Probability help! (normal dist)
« on: August 29, 2012, 10:08:39 pm »
0
Hey all!

i'll just get to the point, I need help with the following question (well just part b)

The amount of a certain chemical in a type A cell is normally distributed with mean of 10 and a standard deviation of 1, while the amount in a type B cell is normally distributed with a mean of 14 and a standard deviation of 2. To determine whether a cell is a type A or a type B, the amount of chemical in the cell is measured and the cell is classified as a type A if the amount is less than a specified value c, and as being of type B otherwise.

a) If c=12 calculate the probability that a type A cell will be misclassified, and the probability that a type B cell will be misclassified.

b) Find the value of c for which the two probabilities of misclassification are equal.

Thanks in advance,
:D
2012: Methods [47] | Chinese SL [35]
2013: Specialist [48] | Chemistry [41] | Physics [44] | English Language [40]
ATAR: 99.55

BubbleWrapMan

  • Teacher
  • Part of the furniture
  • *
  • Posts: 1110
  • Respect: +97
Re: Probability help! (normal dist)
« Reply #1 on: August 29, 2012, 10:40:00 pm »
+1
We have and

a) If A>12 then it will be misclassified, and if B<12 it will be misclassified, so you need to find and using CAS

b)







« Last Edit: August 29, 2012, 10:43:22 pm by ClimbTooHigh »
Tim Koussas -- Co-author of ExamPro Mathematical Methods and Specialist Mathematics Study Guides, editor for the Further Mathematics Study Guide.

Current PhD student at La Trobe University.

barydos

  • Victorian
  • Forum Obsessive
  • ***
  • Posts: 314
  • Respect: 0
  • School: Nossal High School
  • School Grad Year: 2013
Re: Probability help! (normal dist)
« Reply #2 on: August 30, 2012, 09:51:43 am »
0
thank you, you're the best! :D:D:D:D
2012: Methods [47] | Chinese SL [35]
2013: Specialist [48] | Chemistry [41] | Physics [44] | English Language [40]
ATAR: 99.55