Let  $\overrightarrow a = \widehat i - 2\widehat j + 3\widehat k$,   $\overrightarrow b = \widehat i + \widehat j + \widehat k$   and   $\overrightarrow c $   be a vector such that   $\overrightarrow a + \left( {\overrightarrow b \times \overrightarrow c } \right) = \overrightarrow 0 $   and   $\overrightarrow b \,.\,\overrightarrow c = 5$. Then the value of   $3\left( {\overrightarrow c \,.\,\overrightarrow a } \right)$   is equal to _________.