Answer:
3 times a value is equal to twice as much as it's predecessor.
1013.1
from calculator built in on chrome
I wasn't sure whether marked up meant increased or like discounted so ill show you step by step.
10% is $5.
20% would be $10 because it is double the price of 10%.
Therefore if you meant it is 20% more than the original it would be $60.
If you meant it would be 20% less is would be $40.
Sorry its not much help but i wanted to do the best i could.
