8)
a+b=26*2=52
b+c=34*2=68
a+c=30*2=60
2(a+b+c)=52+68+60
a+b+c=180/2
a+b+c=90
a=90-68=22
b=90-60=30
c=90-52=38
9)
c₁ umple 1 bazin in 1 ora(60min) ⇒ 3 ore 3 bazine
c₂ umple 1 bazin in 1,5 ora(90min) ⇒ 3 ore 2 bazine
c₁ umple in 6 minute 1/60 *6 min =1/10 din bazin
c₂ umple in 9 minute 1/90 *9 min =1/10 din bazin
deci in cele 6+9 minute s-a umplut 1/10+1/10=2/10=1/5 din bazin
a ramas de umplut 1-1/5=4/5 din bazin
c₁ + c₂
3 ore .............5 bazine
x ore ...........4/5 bazin
x=(3*4/5 )/5=0,48 ore
0,48 ore x60 min/ora=28,8 minute
0,8 minx60sec/min=48"
0,48 ore = 28' 48"
