how many diff. 4-digit numbers if no digits repeated?

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janig73
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how many diff. 4-digit numbers if no digits repeated?

Postby janig73 » Sun Nov 07, 2010 3:16 am

How many different 4 digit numbers are there if no digit is repeated?

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stapel_eliz
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Postby stapel_eliz » Fri Nov 12, 2010 2:44 pm

janig73 wrote:How many different 4 digit numbers are there if no digit is repeated?

How many options do you have for the first digit?

How many options are left for the second digit?

How many options are left for the third digit?

How many options are left for the last digit?

Multiplying, how many options are there, in total? :wink:


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