Question

daca a supra 0,4=b supra 0,5=c supra 0,6 si 4a+5b+6c=77 atunci a+b+c=?

Answer 1

a/0,4=b/0,5=c/0,6 = k
a/0,4=k => a = 0,4*k
b/0.5=k => b=0.5*k
c/0.6=k=>c=0.6*k
4a+5b+6c= 4*0.4*k+5*0.5*k+6*0.6*k=1.6k+2.5k+3.6k=7.7k = 77 => k=77/7.7 = 10
=> a=4
b=5
c=6
=> a+b+c=4+5+6=15