Find how many five -digit numbers can be forms from 1,2,3,4,5

henryb

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Joined
Apr 24, 2019
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Find how many five-digit numbers can be formed from digs 1, 2, 3, 4, 5, if
(a)the numbers formed must be odd,
(b)the numbers formed must be divisible by 4,
(c)the odd digits must occupy even positions (i.e. 2nd and 4th) and the even digits must occupy odd positions (i.e. 1st, 3rd and 5th).
 

pka

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Jan 29, 2005
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Find how many five-digit numbers can be formed from digs 1, 2, 3, 4, 5, if
(a)the numbers formed must be odd,
(b)the numbers formed must be divisible by 4,
(c)the odd digits must occupy even positions (i.e. 2nd and 4th) and the even digits must occupy odd positions (i.e. 1st, 3rd and 5th).
The way this question is worded there are two possible readings:
1) digits can be used more than once.
OR 2) each digit is used once and only once.
WHICH IS IT?
 

henryb

New member
Joined
Apr 24, 2019
Messages
7
The way this question is worded there are two possible readings:
1) digits can be used more than once.
OR 2) each digit is used once and only once.
WHICH IS IT?
I solved it. Thank you anyway.
 
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