Question

What is the greatest possible perimeter of an obtuse triangle, each of whose side lengths is a whole number of inches less than or equal to 100?

Answer 1

It is impossible to construct an obtuse triangles 
with all sides less than 100. The reason is that 
one of the sides "must" be greater than 100 in 
order to the triangle to be obtuse.  

Answer 2

It is not possible to make an obtuse triangle whose sides are less than or equal to 100. This is because in order to make an obtuse triangle, you have to get a side length that is greater than 100.