Question

Va rog ex 13 si 25 va dau 100 de puncte si coroana

Answer 1

13.(a,b,c)d.p.(5,6,10)=>a/5=b/6=c/10 (amplificam cu 3 la numitor)
(c,d,e)d.p(3,8,12)=>c/3=d/8=e/12  (amplificam cu 10 la numitor)
a/15=b/18=c/30=d/80=e/120=k=>a=15k , b=18k,c=30k,d=80k,e=120k
a+b+c+d+e=200
15k+18k+30k+80k+120k=200
263k=200=>k=0,76
a=0,76*15=11,4
b=13,68
c=22.8
d=60,8
e=91.2
25.(a+b+c)+(a+b+c)x8/100=9072

{a,b,c}dp{4,6,14}
a/4=b/6=c/14=k
a/4=k⇒a=4k
b/6=k⇒b=6k
c/14=k⇒c=14k
inlocuim in I relatie
(4k+6k+14k)+(4k+6k+14k)x8/100=9072
24k+24kx8/100=9072
24k+48k/25=9072
(24kx25+48k)/25=9072
648k=9072x25
k=226800/648
k=350
a=4k=4x350=1400
b=6k=6x350=2100
c=14k=14x350=4900
a) prima persoana a depus 1400 lei
II pers:2100 lei
III pers:4900 lei

b) dupa un an aveau in banca:
I pers : 1400+1400x8/100=1400+112=1512 lei
II pers: 2100+2100x8/100=2100+168=2268 lei
III pers: 4900+4900x8/100=4900+392=5292 lei
1512+2268+5292=9072 lei

c)p/100x5292=1512+2268
5292p/100=3780
5292p=3780x100
p=378000/5292
p=71,42....≈71%