Question

a$\frac{a}{0.4} = \frac{b}{0.5} = \frac{c}{0.6}$ 4a+5b+6c = 77 calculati a + b + c = ?

Answer 1

0,4=4/10=2/5
a/2/5= 5a/2

0,5=5/10=1/2
b/1/2= 2b

0,6= 6/10= 3/5
c/3/5=5c/3

5a/2 =2b =5c/3
5a/2=2b
a=2*2b/5= 4b/5

2b=5c/3
c=2b*3/5=  6b/5

4a+5b+6c=77
4*4b/5 +5b + 6*6b/5=77
16b/5 +5b +36b/5=77 aducem la acelasi numitor
16b+25b+36b=385
77b=385
b=5

a=4*5/5= 4
c=6*5/5=6

a+b+c=4+6+5=15