Răspuns :
1)r=5x1=5
2)r=5x2=10
3)r=5x3=15
4)r=5x4=20
5)r=5x5=25
6)r=5x6=30
7)r=5x7=35
8)r=5x8=40
9)r=5x9=45
2)r=5x2=10
3)r=5x3=15
4)r=5x4=20
5)r=5x5=25
6)r=5x6=30
7)r=5x7=35
8)r=5x8=40
9)r=5x9=45
5 x r < 45
r < 45 : 5
r < 9 ⇒ r ∈ ( - ∞, 8)
r < 9 ⇒ r = ( 0, 1, 2, 3, 4, 5, 6, 7, 8) → pentru clasele primare
r < 45 : 5
r < 9 ⇒ r ∈ ( - ∞, 8)
r < 9 ⇒ r = ( 0, 1, 2, 3, 4, 5, 6, 7, 8) → pentru clasele primare