Question

Aflati a,b,c stiind ca a si b sunt invers proportionale cu 0,(2), respectiv 1,(1), b si c sunt direct proportionale cu 3, respectiv 2, iar a+2b+3c=54​

Answer 1

a × 0,(2) = b × 1,(1)

a × 2/9 = b × 10/9 => 2a/9 = 10b/9 => 2a = 10b => a = 5b

b/3 = c/2 = K => b = 3k, c = 2k

a = 5b = 5 × 3k = 15k

a + 2b + 3c = 54

15k + 6k + 6k = 54

27k = 54

k = 2

a = 15k = 15 × 2 = 30

b = 3k = 3 × 2 = 6

c = 2k = 2 × 2 = 4