Turn on thread page Beta
    • Thread Starter
    Offline

    5
    ReputationRep:
    Hi guys, needing some help with some nCr, nPr and factorial S1 stuff here;

    At a small branch of the Mid-West Bank, the manager has a staff of 12, consisting of 5 men and 7 women including a Mr Brown and Mrs Green. The manager receives a letter from Head Office saying that 4 of his staff are to be made redundant. In the interests of fairness the manager decides to select the 4 staff at random.
    (i) How many different selections are possible?
    (ii) How many of these selections include both Mr Brown and Mrs Green?
    (iii) Write down the probability that both Mr Brown and Mrs Green will be made redundant.

    I can do part i but part ii I have no idea how to do.

    Thanks
    •  Official Rep
    Offline

    15
    ReputationRep:
     Official Rep
    Sorry you've not had any responses about this. Are you sure you've posted in the right place? Here's a link to our subject forum which should help get you more responses if you post there.
    Offline

    20
    ReputationRep:
    (Original post by Chonty)
    Hi guys, needing some help with some nCr, nPr and factorial S1 stuff here;

    At a small branch of the Mid-West Bank, the manager has a staff of 12, consisting of 5 men and 7 women including a Mr Brown and Mrs Green. The manager receives a letter from Head Office saying that 4 of his staff are to be made redundant. In the interests of fairness the manager decides to select the 4 staff at random.
    (i) How many different selections are possible?
    (ii) How many of these selections include both Mr Brown and Mrs Green?
    (iii) Write down the probability that both Mr Brown and Mrs Green will be made redundant.

    I can do part i but part ii I have no idea how to do.

    Thanks
    for ii) you have removed Mr B & Mrs G from the list. you now have to choose 2 people from the remaining 10.
    • Thread Starter
    Offline

    5
    ReputationRep:
    (Original post by the bear)
    for ii) you have removed Mr B & Mrs G from the list. you now have to choose 2 people from the remaining 10.
    Thanks
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: November 7, 2017
Poll
Do you think parents should charge rent?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

Equations

How to use LaTex

Writing equations the easy way

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.