Math CentralQuandaries & Queries


Question from Rajesgy:

Guess the 5 digit number
Hint: Number is divisible by 2
Average of all numbers is 5
Last 2 digit is divisible by 7 and the number is less than 50000
Only one odd digit


You didn't say if the 5 digits must be different. I expect they do.

The number is divisible by 2: This means its units digit must be even.

Average of all its digits is 5: What does this tell you about the sum of the 5 digits?

The number formed by the last 2 digit is divisible by 7:

Consider the 2 digit multiples of 7: 07, 14, 21, ... delete those that have an odd units digit.

Is this enough help to answer the question?

Is there more than one correct answer?


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