Răspuns :
a. [13 + (5×4+1)/4 + (2×4+3)/4]/3 = (13 + 21/4 + 11/4)/3 = (13 + 32/4)/3 = (13 + 8)/3 = 21/3 = 7
b. [4,49 + (7×20+1)/20 + (5×2+1)/2]/3 = (4,49 + 141/2) + 11/2)/3 = (4,49 + 152/2)/3 = (4,49 + 76)/3 = 80,49/3
c. [(32×9+7)/9 + (5×9+5)/9 + (5×9+1)/9 + (156-15)/9]/4 = (295/9 + 50/9 + 46/9 + 141/9)/4 = 532/9/4 = 133/9
b. [4,49 + (7×20+1)/20 + (5×2+1)/2]/3 = (4,49 + 141/2) + 11/2)/3 = (4,49 + 152/2)/3 = (4,49 + 76)/3 = 80,49/3
c. [(32×9+7)/9 + (5×9+5)/9 + (5×9+1)/9 + (156-15)/9]/4 = (295/9 + 50/9 + 46/9 + 141/9)/4 = 532/9/4 = 133/9