1. a) 2,5 = 25/10 = 5/2
b) 1,25 = 125/100=5/4
c) 2,(3) = 23/9
2. 17/10 = 1,7
29/100 = 0,29
27/2 = 13,5
23/8 = 2,875
3. a) 2/3 - 4/3 • 3/5 = 2/3 - 4/5 (se simplifică 3 cu 3) = -2/5
b) 1/2 : 3/4 + 1/9 = 1/2 • 4/3 + 1/9 = 2/3 + 1/9 (aducem la acelasi numitor, numitor comun 3) = 6/9 + 1/9 = 7/9
c)(5/7)^2 = 25/49
d) (2/3)^3 = 8/27
4) a) √48 = √16•3= 4√3
b) √75 = √25•3 = 5√3
c) √288 = √36•8 = 6√8 = 6√4•2 = 12√2
d) √98 = √49*2 = 7√2
5. a) 3√5 = √9•5 = √45
b) 2√11 = √11•4 = √44
c) 10√3 = √100•3 = √300
