Question
The ratio of the number of red erasers to blue erasers is 7 : 5. After Billy gives away 10 red erasers and buys another 20 blue erasers, there is equal number of red erasers and blue erasers. How many erasers does Billy have now?
3 m

Click button first when a symbol is required. X

The ratio of the number of red erasers to blue erasers is 7 : 5. After Billy gives away 10 red erasers and buys another 20 blue erasers, there is equal number of red erasers and blue erasers. How many erasers does Billy have now?