1)
2,6; 2,6(5); 2,(65); 2,(6); 2,6(67)
3)
[tex]\bf 3(2x-5)+4x=7x+2[/tex]
[tex]\bf 6x-15+4x=7x+2[/tex]
[tex]\bf 10x-15=7x+2[/tex]
[tex]\bf 10x-7x = 2+15[/tex]
[tex]\bf 3x=17[/tex]
[tex]\boxed{\bf x=\dfrac{17}{3} }[/tex]
4)
[tex]\bf 30\%\cdot 500 = 30:100\cdot 500 = 0,3\cdot 500= \boxed{\bf 150}[/tex]
5)
Notam cu x pretul initial
x - 10%·x = x - 70
x - 10:100·x = x - 70
x - 0,10x = x - 70 |+70
0,90x + 70 = x
70 = x - 0,90x
70 = 0,10x |: 0,10
x = 700 lei pretul initial
