If a bag contains 6 green balls and 3 red balls, what the probability of picking out 2 red, with and without replacement.

For the first ball the probability we pick a red ball is the same, it's the number of red balls divided by the total number of balls. Which in this case is 3/9. 

If we replace the balls the chance of picking out a 2nd red ball is still 3/9. So the total probability is 3/9 times 3/9 which is 1/9.

If we don't replace the chosen ball. The probability of picking a second is still the number of red balls divided by the new total number which is 2/8 or 1/4. Therefore the total probability is 1/4 times 3/9 which is 1/12.

TF
Answered by Toby F. Maths tutor

20891 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Express 112 as a product of it's prime factors.


If L1 is y = 3x + 15 and L2 is 3y + 20 = 9x show whether or not L1 and L2 are parallel.


Show me why the product of a squared and a cubed is a to the power of 5.


Determine the coordinates of the intersection point(s) between the line y = x^2 + 4x - 8 and y = - 2x - 17


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences