There are 4 blue balls, 2 red balls, and 5 green balls in a bag. James removes one ball and does not replace it. James removes a second ball. What is the probability that both balls will be the same colour.

Total number of balls = 4 + 2 + 5 = 11 (this is our denominator for first draw)Numerator is the number of each colour. When we remove a ball the denominator and numerator for that colour decrease by 1. P(2 blue) = (4/11)(3/10) = (12/110), P(2 red) = (2/11)(1/10) = (2/110), P(2 green) = (5/11)(4/11) = (20/110)To find the total probability of picking two of the same colour we add these probabilities together then simplify.Total probability = 12/110 + 2/110 + 20/110 = 34/110 = 17/55

CW
Answered by Caleb W. Maths tutor

3597 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Find the value of x in the equation x^2 - 2x + 1 = 0


GCSE: I don't understand how to rationalise denominators


How do I work out the area of a quarter circle with radius 6cm?


Solve the simultaneous equation 2x + y = 18 and x - y = 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