Final answer:
Juno ended up on the 6th floor.
Step-by-step explanation:
Juno started at the ground floor (0 floor) and went up 26 floors, which would take him to the 26th floor. He then went down 7 floors from the 26th floor, which would take him to the 19th floor. Next, he went up 3 floors from the 19th floor, which would take him to the 22nd floor. Finally, he went down 16 floors from the 22nd floor, which would take him to the 6th floor. Therefore, Juno ended up on the 6th floor.