Question

Calculati media aritmetica a nr: 
a= 1 supra 2 + 1 supra 3 + .... + 1 supra 1999 
b= 1 supra 2 + 2 supra 3 + .... +1998 supra 1999
c= 1 supra 11 + 1 supra 12 + ...... + 1 supra 2000 
b= 10 supra 11 + 11 supra 12 + ..... +1999 supra 2000

Answer 1

a+b = (1/2 +1/2) +(1/3+ 2/3) +(1/4 + 3/4) +........+(1/1999 + 1998/1999) = 1·1998 =
= 1998
c+d = (1/11 + 10/11) + (1/12 +11/12 ) +......+(1/2000 +1999/2000 ) = 1· 1990= 1990
M = (1998+1990)/4 = 3988/4 = 997