SOLUTION: choosing a local phone number if the exchange is 398 and each of the four remaining digits is different

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Question 1202501: choosing a local phone number if the exchange is 398 and each of the
four remaining digits is different
Answer by josgarithmetic(39632) About Me  (Show Source):
You can put this solution on YOUR website!
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...,and each of the
four remaining digits is different.
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Maybe the missing question was, how many such numbers are possible?
This information here should be useful in your path to answering. 

PLACE        HOW MANY CHOICES
  7            10
  8             9
  9             8
 10             7