There were 100 coins in a box. The ratio of coins to notes was 4 : 7.
After 25 coins were removed and some notes were added to the box,
the ratio of coins to notes became 1 : 3.
How many notes were added to the box?

Jody bought 20 shares of amazon at the close price of $121.00. she bought 20 more shares a year later at the price of $127.00. two years later, she sold all of her shares at the price of $133.00. her broker charges $50 for each transaction. after all of these transactions, how much money did jody make?