p= nr cazuri favorabile / nr cazuri posibile
nr ce îndeplinesc conditia sunt : 10, 11, 12, 13, 14 ,15, 16, 17, 18, 19,
20, 21, 22, 23, 24, 25, 26, 27, 28,
31, 32, 33,34,35,36,37,
40, 41, 42, 43, 44, 45, 46,
50, 51, 52, 53, 54, 55,
60, 61, 62, 63, 64,
70, 71, 72, 73,
80, 81, 82,
90, 91
nr cazuri favorabile = 2+3+4+5+6+7+8+9+10= (2+10)×9 ÷2= 12÷2×9=6×9=54
nr cazuri posibile = 99-10+1= 90
p=54/90= 3/5
