Can P(C) be found using the method shown in the photo?

  • Thread starter Thread starter desmond iking
  • Start date Start date
  • Tags Tags
    Probability
desmond iking
Messages
284
Reaction score
2

Homework Statement



i have problem of finding P(C) , why can't i use the method as in the photo to find P(C) beacuse 1-(all unused stamps are missing)= at least 1 use stamps is missing.

Homework Equations





The Attempt at a Solution

 

Attachments

  • IMG_20140722_015315[1].jpg
    IMG_20140722_015315[1].jpg
    32.5 KB · Views: 430
  • DSC_0044[1].jpg
    DSC_0044[1].jpg
    27.4 KB · Views: 420
Physics news on Phys.org
C is the event at least one of the used stamps is missing.

"all unused stamps are missing" would mean there are 14 stamps missing - but the problem statement says only three are missing.

Did you mean, "all missing stamps are "unused"" - but that is not correct either since at least one of them has to be "used".

even C is the same as "at most two of the missing stamps are unused"

You need to comment your working.
 
Ya I mean all the 3 stamps missing are unused.
 
So if you write: D:=event all three missing stamps are unused, then you want to argue that P(C)=1-P(D), is that what you are saying?
 

Thread 'Prove that the integral is equal to ##\pi^2/8##'

Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
View full post »

Similar threads

Finding Non-Trivial Solution(s) For 3x3 Matrix
Replies
9
Views
2K
Probability Theory, work check
Replies
4
Views
1K
How to calculate the monthly interest rate?
Replies
12
Views
2K
Use Wronskian method in solving the given second order differential equation
Replies
7
Views
2K
How can I convert this function into a differential equation?
Replies
4
Views
1K
Are Coin Toss Events A, B, and C Independent?
Replies
1
Views
2K
Probability of equal roots in equation
Replies
10
Views
2K
Finding 2 solutions of this Bessel's function using a power series
Replies
8
Views
2K
Use greedy vertex coloring algorithm to prove the upper bound of χ
Replies
0
Views
109
What are the values of the remaining stamps?
Replies
3
Views
1K

Hot Threads

Recent Insights

Back
Top