In a stack of CDs, there are 3 types: Rock, Pop and Jazz. There are 2 Rock CDs, x Pop CDs, and (2x+5) Jazz CDs. A CD is chosen at random. If the probability it is Rock is 1/20, work out the probability it is Jazz.

Number of Rock CDs = 2Total Number of CDs = 2 + x + (2x+5) = 3x + 7Probability of Rock CD = 2/(3x + 7) = 1/202/(3x + 7) = 1/2040 = 3x + 7x = 11Number of Jazz CDs = 2x + 5 = 27Total Number of CDs = 3x + 7 = 40Probability of Jazz = 27/40

VL
Answered by Vinh L. Maths tutor

2879 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

How do you calculate the sum of all internal angles of a regular polygon?


For a cuboid, the longest side is two units more than the shortest side, and the middle length side is one unit longer than the shortest side. The total surface area of the cuboid is 52 units². (a) Construct an equation to calculate the surface area.


A voucher takes 12% off a bill at a restaurant. After using the voucher, the bill for a meal is £31.68. How much was the bill before using the voucher?


Solve the simultaneous equation: 3x + 2y = 4 , 4x + 5y = 17


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences