Answer:
KC to StL = 300
KC to Den = 600
Explanation:
KC to StL was the base distance, so we'll call that x.
KC to Denver is twice as long, so we'll call that 2x.
If we add the together is is 900 miles total.
x + 2x = 900 Combine like terms
3x = 900 Divide by 3
x = 300
If x is 300, then 2x is 600.