My Math Forum  

Go Back   My Math Forum > High School Math Forum > Probability and Statistics

Probability and Statistics Basic Probability and Statistics Math Forum

Thanks Tree1Thanks
  • 1 Post By romsek
LinkBack Thread Tools Display Modes
June 7th, 2019, 07:21 AM   #1
Joined: Apr 2017
From: India

Posts: 73
Thanks: 0


This question is from my examination paper:

One bag contains 4 white and 3 black balls
and a second bag contains 3 white and
5 black balls. One ball is drawn from the
first bag and placed unseen in the second
bag. What is the probability that a ball now
drawn from the second bag is black ?

My final answer was 38/63.

Can someone please check that for me whether I answered it correctly or not?
shashank dwivedi is offline  
June 7th, 2019, 09:47 AM   #2
Senior Member
romsek's Avatar
Joined: Sep 2015
From: USA

Posts: 2,549
Thanks: 1399

$\dfrac 4 7\dfrac 5 9 + \dfrac 3 7 \dfrac 6 9 = \\

\dfrac{20}{63}+\dfrac{18}{63} = \dfrac{38}{63}$

well done
Thanks from shashank dwivedi
romsek is offline  
June 7th, 2019, 10:29 AM   #3
Senior Member
Joined: Dec 2015
From: somewhere

Posts: 634
Thanks: 91

I worship cats too .
idontknow is offline  

  My Math Forum > High School Math Forum > Probability and Statistics


Thread Tools
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
The probability of this being another probability question Devans99 Probability and Statistics 4 June 25th, 2018 01:06 PM
Continuous probability; find probability density function rivaaa Advanced Statistics 5 November 5th, 2015 01:51 PM
probability set theory - probability of x out of n events hbonstrom Applied Math 0 November 17th, 2012 07:11 PM
Joint probability density function, probability token22 Advanced Statistics 2 April 26th, 2012 03:28 PM
Probability (probability mass function,pmf) naspek Calculus 1 December 15th, 2009 01:18 PM

Copyright © 2019 My Math Forum. All rights reserved.