Math Is Fun Forum

mantastrike

Member

Registered: 2011-04-24

Posts: 64

Please help me again with my math homework!!

Find the number of different four-digit numbers which can be formed from the digits 1, 2, 3, 4, 5, 6, 7, if each digit:

a) Can only be used once.

b) Can be used more than once but the most significant digit can only use three different digits

thank you!! Sorry if I want people to do my homework for me but I don't have time...
PLEASE HELP ME!!

Bob

Administrator

Registered: 2010-06-20

Posts: 10,164

Re: Please help me again with my math homework!!

Have you got time to look at

http://www.mathsisfun.com/combinatorics/combinations-permutations.html

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Please help me again with my math homework!!

Hi mantastrike;

Sorry if I want people to do my homework for me but I don't have time...

It bothers me a lot to here that. You must make time for your homework! Your future depends on it. You have been finding time to post these questions on other forums. You are finding time to post them here. Please explain what you do not understand clearly and help will be provided. Being given answers is very harmful to you.

If you were in a jam, I would be more motivated to answer the questions but homework is personal work. It must be done by you.

Put your first steps down. Try to do it on your own and post what you have done. Then you can be helped in the correct manner.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.