The second rocket goes 500*2=<<500*2=1000>>1000 feet

So the total height is 500+1000=<<500+1000=1500>>1500 feet

# Answer

1500
Question:
John builds a model rocket that can travel 500 ft in the air.  He builds a second rocket that can travel twice as high.  What is the combined height of the two rockets?
Answer:
Let's think step by step.

user
1500
John builds a model rocket that can travel 500 ft in the air.  He builds a second rocket that can travel twice as high.  What is the combined height of the two rockets?
train