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anonymous
 one year ago
The number of twodigit positive integers for which the units digit is not equal to the tens digit.
anonymous
 one year ago
The number of twodigit positive integers for which the units digit is not equal to the tens digit.

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misty1212
 one year ago
Best ResponseYou've already chosen the best response.1my guess is \(81\) reason as follows: you have nine choices for the tens place digit (it cannot be zero) then another 9 choices for the ones place (it can be zero, but it cannot be the tens digit)

misty1212
 one year ago
Best ResponseYou've already chosen the best response.1by the counting principle you get \(9\times 9=81\)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ouuuuu niceeeee okay got it thanks!

misty1212
 one year ago
Best ResponseYou've already chosen the best response.1course i could be wrong maybe @geerky42 has a different answer

geerky42
 one year ago
Best ResponseYou've already chosen the best response.1There are \(9910+1 = 90\) two digits numbers. Now exclude numbers where tens digit and unit digit are same; 11, 22, 33, 44, ..., 99 There are \(9\) of them. So you have \(909 = \boxed{81}\) So @misty1212 is correct.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0hey why do u exclude the 11, 22,33,44 etc.?????

misty1212
 one year ago
Best ResponseYou've already chosen the best response.1for which the units digit is not equal to the tens digit.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0but doesnt that just mean 10, 20, 30, 40 etc?

geerky42
 one year ago
Best ResponseYou've already chosen the best response.1No. "units digit is equal to the tens digit" means 11, 22, 33, etc. So here, we have "units digit is NOT equal to the tens digit", which means 10, 12, 13, ..., 20, 21, 23, ..., 31, 32, 34, ..., etc.

geerky42
 one year ago
Best ResponseYou've already chosen the best response.1We counted ALL two digits numbers, then we uncounted number where "units digit is equal to the tens digit"
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