SOLUTION: Counting numbers are to be formed using only the digits 1, 8, and 5. Determine the number of different possibilities for​ two-digit numbers.

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Question 1161538: Counting numbers are to be formed using only the digits 1, 8, and 5. Determine the number of different possibilities for​ two-digit numbers.
Found 2 solutions by ikleyn, solver91311:
Answer by ikleyn(52781)   (Show Source): You can put this solution on YOUR website!
.

Any of the 3 digits can occupy the first position,

and any of the 3 digits can occupy the second position.


So, if there is no restriction on repeating the digits, then the answer is 3*3 = 9.


If, in opposite, THERE IS such a restriction, then the answer is 3*2 = 6.



The fact that the problem does not formulate the presence ot the absence of the restriction, is the author's FAULT.

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Solved, explained, answered and completed.



Answer by solver91311(24713)   (Show Source): You can put this solution on YOUR website!


You don't specify whether digits can be repeated in the two-digit number, so not being specifically prohibited, there is no reason to assume that they are not allowed. Hence there are three ways to select the first number and for each of those three ways, there are three ways to select the second number. I'm going to go out on a limb here and assume that you can manage 3 times 3.


John

My calculator said it, I believe it, that settles it
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