Question

Calculati media aritmetica a numerelor:

a) 12 intregi 2/5 si 17 intregi 3/5
b) 45 intregi 3/6 si 12 intregi 1/4
c) 7/15 si 12 intregi 1/5

Answer 1

a) (12 si 2/5 + 17 si 3/5) : 2 = (62/5+88/5) : 2= 150/5 : 2 = 30:2 = 15
b) (45 si 3/6 + 12 si 1/4) : 2 = (45 si 1/2 + 49/4) : 2 = (91/2+49/4) : 2 = (182/4+49/4):2 = 231/4 x 1/2 = 231/8 = (224+7)/8 = 28 si 7/8
c) (7/15 + 12 si 1/5) : 2 = (7/15 + 61/5) : 2 = (7/15+183/15):2 = 190/15 : 2 = 38/3 x 1/2 = 19/3 = (18+1)/3 = 6 si 1/3