a) xy= 21* 0,(6)
xy = 21* 6/9
xy= 21 * 2/3
xy = 7*2 => xy=14
b) xy=42*1,(3)
xy= 42 * (1+ (3/9))
xy = 42 * (3/3+ 1/3)
xy= 42 * 4/3
xy= 14*4 => xy= 56
c) xy= 30 * 0,8(3)
xy= 30 * ( (83-8)/90 )
xy= 30 * 75/90
xy= 75/3 => 25
d) xy = 24* 1,1(6)
xy = 24 * (1 + (16-1)/90)
xy = 24 * (1 + 15/90)
xy= 24 *( 6/6 + 1/6)
xy= 24 * 7/6
xy = 7*4 => xy= 28
* este inmultire si / este linie de fractie
