Resolving vertically upwards
\displaystyle \begin{align} & {{T}_{1}}\cos {{50}^{\circ }}-mg=0 \\ & \\ & {{T}_{1}}=\frac{mg}{\cos {{50}^{\circ }}}=\frac{490}{0\textrm{.}643}=762\ \text{N} \\ \end{align}
