Question

se considera sirul de rapoarte egale 2a/3=5b/6=8c/9 si a+b+c=51. Aflati numerele a, b si c

Answer 1

2a/3 = 5b/6 = 8c/9 = k

Atunci 2a = 3k, adica a = 3k/2

5b = 6k, adica b = 6k/5

8c = 9k, adica c = 9k/8

Dar a+b+c = 51, adica:

3k/2 + 6k/5 + 9k/8 = 51

60k/40 + 48k/40 + 45k/40 = 51

153k/40 = 51

153k = 40*51

k = 40*51/153 = 40*51/3*51 = 40/3

Revenim la sirul de rapoarte:

2a/3 = 40/3 => 2a = 40 => a = 20

5b/6 = 40/3 => 15b = 240 => b = 16

8c/9 = 40/3 => 24c = 360 => c = 15

Answer 2

bafta multa..................................