a) ma1 =(a+b)/2=5
a+b=2*5=10
ma2=(c+d+e)/3=25
c+d+e=3*25=75
ma3=( f+g+h+i+j)/5=200
f+g+h+i+j=5*200
f+g+h+i+j=1000
ma a celor 10 numere este (a+b+c+d+e+f+g+h+i+j)/10= (10+75+1000)/2= 1085/2=
=542,5
b) map= (1/3 *2 + 1/6 *3 + 3/8 *4)/(2+3+4)=
=(2/3+1/2 +3/2)/9 aducem la acelasi numitor in paranteza
=(4+3+9)/6/9=
=16/6 *1/9=
=8/3 *1/9= 8/27