Find the simplest value of $$2\sqrt {50} + \sqrt {18} - \sqrt {72} $$     (given √2 = 1.414).

$$\eqalign{ & 2\sqrt {50} + \sqrt {18} - \sqrt {72} \cr & \Rightarrow 2 \times 5\sqrt 2 + 3\sqrt 2 - 6\sqrt 2 \cr & \Rightarrow 13\sqrt 2 - 6\sqrt 2 \cr & \Rightarrow 7\sqrt 2 \cr & \Rightarrow 7 \times 1.414 \cr & \Rightarrow 9.898 \cr} $$