6,9,8 hope you have a great day :D
The chart on the side should help you out. The width of a doorway is approximately 1 meter and the height of a skyscraper is 1,000 meters. Divide the height of the skyscraper by the width of the doorway to get your answer. It would take 1,000 door widths to make up the height of a skyscraper, so the height of the skyscraper is 1,000 times the width of the doorway.
X is 1 over 10. 10 squared is 100. X is 7. The third root of 343 is 7.