Răspuns :
cifra 9 apare in componenta urmatoareler numere:
9,19,29,39,49,59,69,79,89, 90,91,92,93,94,95,96,97,98,99
adica de 20 de ori
9,19,29,39,49,59,69,79,89, 90,91,92,93,94,95,96,97,98,99
adica de 20 de ori