Level 3
The ratio of the number of blue stickers to red stickers is 5 : 2.
After Adam gives away 10 blue stickers and gives away 20 red stickers,
the ratio becomes of the number of blue stickers to red stickers is 9 : 2.
How many stickers does Adam have now?
Level 3
The ratio of the number of blue stickers to red stickers is 5 : 2.
After Adam buys another 20 red stickers and gives away 10 blue stickers,
the ratio becomes of the number of blue stickers to red stickers is 3 : 2.
How many stickers does Adam have now?
Level 3
A coin bank contains some twenty-cent and fifty-cent coins in the ratio of 2 : 5.
When 10 fifty-cent coins are taken out and exchanged with some twenty-cent coins of the same value,
the ratio became 8 : 9.
Find the sum of money in the coin box in dollars.
