Question

CALCULATI: (1+2+3+....+2014):2015

Answer 1

$\displaystyle (1+2+3+...+2014):2015= \frac{2014(2014+1)}{2} :2015= \\ \\ = \frac{2014 \times 2015}{2} :2015= \frac{4058210}{2} :2015=2029105:2015=1007$