Question

Cate numere de doua cifre distincte exista?CU REZOLVARE
DAU COROANA!!!

Answer 1

Nr. de la 1 la 100  sunt : 100 nr. din care scadem 10 nr.(de la 1 la 9 si 100) si 9 nr. cu cifre identice (11 ;22 ; 33 ; 44 ; 55 ; 66 ; 77 ; 88 ; 99)
100-10-9=81
R: sunt 81 de nr. din doua cifre diferite

Answer 2

10 ,12 ,13,14,15,16,17,18,19,20,21,23,24,25,26,27,28,29,30,31,32,34,35,36,37,   38,39,40,41,42,43,45,46,47,48,49,50,51,52,53,54,56,57,58,59,60,61,62,63, 64,   65,67,68,69,70,71,72,73,74,75,76,78,79,80,81,82,83,84,85,86,87,89,90, 91,92,93,94,95,96,97,98 .

Sunt 92 de numere .