The number of points, having both co-ordinates as integers, that lie in the interior of the triangle with vertices $( 0,0 ) , ( 0,41 )$ and $( 41,0 )$ is (1) 780 (2) 901 (3) 861 (4) 820
The number of points, having both co-ordinates as integers, that lie in the interior of the triangle with vertices $( 0,0 ) , ( 0,41 )$ and $( 41,0 )$ is\\
(1) 780\\
(2) 901\\
(3) 861\\
(4) 820