Calculate the Iterated Integral $$\int _ { 0 } ^ { 6 } \int _ { 0 } ^ { 3 } \sqrt { 25 x + 25 y } d x d y$$

Short Answer

Calculate the iterated integral. Round your answer to two decimal places.
$$\int _ { 0 } ^ { 6 } \int _ { 0 } ^ { 3 } \sqrt { 25 x + 25 y } d x d y$$