90001
The 1987 postcard of Yankee Stadium would be worth about $5,-$10. in near/mint condition. With the new Stadium opening in 2009 the value will rise in the coming years, but not by much.
2009 - 1987 = 22
2009 - 1987 = 22
you will surly get around 90000 to 100000
Using the average inflation rate over the period between 1972 and 2009 of 4.62: * $1,000 in 1972 dollars would be worth $5,318 in 2009 dollars * $1,000 in 2009 dollars would be worth $188 in 1972 dollars.
$100.00
It would be worth 300 pounds. Now what the 1917 owner of the 300 pounds should have done was invest it in stocks, or bonds, or real estate, or even a savings account, and then it would have been worth a lot more than 300 pounds in 2009.
Impossible to answer since you did not identify or describe the firearm.
What cost $50 in 1869 would cost $796.09 in 2009.
If you were born October 17, 1989 you would have turned 22 in 2009.
Subtract 1987 from 2009. The answer is 22.
if it is in good condition right now in 2009 it would be worth around $80 to $125