Question

Afla media aritmetica a nr:
A)1/3 si 5/7
B)3/4 si 5/6 si 2/7
C)1/2 si 1/2 si 4 si 4
D)3/5si 0,2 si 0,8

Answer 1

a)(1/3 + 5/7) : 2 = (7/21 + 15/21) : 2 = 22/21 : 2/1 = 22/21 x 1/2 = 22/42
b)(3/4 + 5/6 + 2/7) : 3 = (126/168 + 140/168 + 48/168) : 3 = 314/168 : 3/1 = 314/168 x 1/3 = 314/504
c)(1/2 + 1/2 + 4 + 4) : 4 = (1 + 4 + 4) : 4 = 9 : 4 = 9/4
d)(3/5 + 0,2 + 0,8) : 3 = (3/5 + 1/1) : 3 = (3/5 + 5/5) : 3 = 8/5 : 3 = 8/5 x1/3 =8/15