Answer
In the first statement, the length of the animal has no unit.
In the second statement, the width of the room (7.36 bleams) is not a definite measurement since we have no understanding of how long, exactly, is a "bleam".
Work Step by Step
To say the length of an animal is 51 doesn't give any units, so the understanding is very limited. After all, an animal of 51 meters is very different from an animal of 51 millimeters. One must use units that others
understand.
It is also a problem to give a measurement with a unit that has no understanding. To know the width of a room is 7.36 bleams is also vague at best, since we have no understanding of how long, exactly, is a "bleam".
