Nina wants to download games for her video game console. Older games cost 100 points and new releases cost 200 points to use. The equation 100a+200b=4000, where a is the number of der games and b is the number of new releases, models the situation. How many older games can she download if she downloads 4 new games? 5 new games?
Replace b with 4: 100a+200(4)=4000. 100a+800=4000. Combine like terms: 100a=3,200. Get the unknown by itself: A=32. She can download 32 old games if she downloads 4 new ones. Same steps: 100a+200(5)=4000. 100a+1000=4000. 100a=3000. A=30. She can download 30 old games if she downloads 5 new ones. :)
