Question

AJUTATI-MA REPEDE!
 VA ROG!!

afe17ba2065f5f188c7ffcdbf0df78d5.rtf

Answer 1

a-mere
b-pere
c-prune
a+b+c=156
a=b+18
c=a-3=b+18-3=b+15
(b+18)+b+(b+15)=156
3b+33=156
3b=156-33
b=123/3
b=41 pere
a=b+18=41+18=59 mere
c=a-3=59-3=56 prune

x-cei calificati
y-cei necalificati
x+y=1500
a=b/3
b/3+b=1500
(b+3b)/3=1500
4b=1500·3
b=4500/4
b=1125 necalificati
a=1500-b=1500-1125
a=375 calificati

a+b=135
a:b=4 rest 5⇒    a=4b+5
4b+5+b=135
5b+5=135
5b=135-5
b=130/5
b=26
a=135-b=135-26
a=109