What is the probability of picking a red ball twice from a bag of 6 blue balls and 3 red balls, without replacement.

The probability of picking a ball from a bag is the number of balls of that colour divided by the total number of balls.

Therefore in the first instance, the probability of a red ball is 3/9 or 1/3rd.

If that ball is now removed the probability of picking a 2nd is 2/8 or 1/4.

Therefore the probability that both these happen is 1/4 * 1/3 which is 1/12. 

TF
Answered by Toby F. Maths tutor

37081 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

A circular table has a diameter 140 cm. Calculate the area of the table in cm^2, leaving your answer as a multiple of pi.


Matt has 3 piles of coins, A , B and C. Altogether there was 72p. Pile B had twice as much as pile A. Pile C had three times as much as pile B. How much money was in Pile C?


Show that (x+2)(x+3)(x+5) can be written in the form ax^3 + bx^2 + cx +d, where a,b, c and d are positive integers


How to factorise a simple linear equation such as '9Y + 6'


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