Question

calculați:
(1) 28/4•8/7+3/5
(2)5/12+5/7•7/8
(3)15/3 - 12/15•1/4
(4)3/8•2/5+5/4•1/2
(5)9/7•2/3 - 14/15•5/21
(6)18/11+2/3•5/4•6
(7)7/12+1/6•5/3-1
(8)6/4•2/11•5/3-4/11
(9)3/20+2/8•4/3+1/3

DAU COROANA..CU TOT CU MODUL DE CALCUL VA ROG​

Answer 1

Răspuns:

Explicație pas cu pas:

(1) 28/4•8/7+3/5 = 28•8/(4•7)+3/5 = (dupa simplificare prin 28 in prima fractie) = 8+3/5 = (am adus la acelasi numitor)= 40/5+3/5= 43/5

(2)5/12+5/7•7/8 =5/12+ 5/8 (am simplificat prin 7)= (am adus la acelasi numitor) = 10/24+15/24= 25/24

(3)15/3 - 12/15•1/4= 5-1/5 (am simplificat in ambele fractii) = (am adus la acelasi numitor) = 25/5-1/5= 24/5

Aceleasi operatii de simplificare si aducere la acelasi numitor au fost aplicate si mai jos

(4)3/8•2/5+5/4•1/2= 3/20+5/8= 6/40+25/40= 31/40

(5)9/7•2/3 - 14/15•5/21 = 6/7 - 2/9= (63-14)/9 = 39/9

(6)18/11+2/3•5/4•6 = 18/11+ 5= (18+55)/11 = 73/11

(7)7/12+1/6•5/3-1= 7/12+5/18-1 = (21+10-36)/36 = -5/36

(8)6/4•2/11•5/3-4/11 = 5/11-4/11= 1/11

(9)3/20+2/8•4/3+1/3