What's the total height of a 17-story building that measures 4 meters 2 decimeters 17 centimeters per story?

Well, one story is 4m 2dm and 17 cm.

now, there are 100 centimeters in 1 meter, so in 4 meters there are 400 cm then.

now, there are 10 decimeters in 1 meter, therefore, 10 centimeters in 1 dm, so in 2 dm is then 20 cm.

in 17 centimeters, is just 17 cm :).

so, the 1 story of the building is 400 + 20 + 17 centimeters, or 437 cm.

now, the building has 17 stories, so 17 * 437 or 7429 cm.

which will then be 7400 cm or 74 meters.

and 

20 cm or 2 dm.

and

 9 cm.

so, 74 meters, 2 decimeters and 9 centimeters.