Răspuns:
Explicație pas cu pas:
[ x; y; z] d.p. [ 2; 8; 10]
=> x/2 = y/8 = z/10 = k -> coeficient de proportionalitate
=> x = 2 k; y = 8 k si z = 10 k
_________________________
√(x×y) = 12 -> media geometrica a primelor doua numere ( x; y)
√(2k×8k) = 12
√(16k²) = 12
4k = 12 => k = 12 : 4 => k = 3
_________________________
x = 2k = 2×3 => x = 6
y = 8 k = 8×3 => y = 24
z = 10 k = 10×3 => z = 30
____________________
Ma= ( x + y + z ) / 3 = ( 6+24+30)/3 = 60/3 = 20 -> media aritmetica a celor trei numere
