Răspunsuri

2014-06-24T12:02:42+03:00
80% din b =f

80% * b= f

80/100* b=f

4/5 * b= f

f=4b/5

f+b=27
4b/5 +b=27   aducem la acelasi numitor

4b+5b=135
9b=135
b=15

f=27-15
f=12
1 5 1