Question

A store sells used and new video games. New video games cost more than used video games. All used video games cost the same. All new video games also cost the same. ​ Omar spent a total of $84 on 4 used video games and 2 new video games. Sally spent a total of $78 on 6 used video games and 1 new video game. Janet has $120 to spend. ​ Enter the number of used video games Janet can purchase after she purchases 3 new video games.

Answer 1

Answer: Janet can purchase 5 used video games after purchasing 3 new ones.

Step-by-step explanation: Use simultaneous equations to find the actual cost of new and used video games.

Let x be the cost of used video games.

Let y be the cost of new video games.

From the information above

4x+2y=$84 ... equation 1

6x+y=$78 ... equation 2

y=$78-6x ... equation 3

Substituting equation 3 into equation 1 you get:

4x+2(78-6x) = 84

4x+156-12x =84

8x = 72

×= $9 therefore y=$24.

Janet has therefore already used $24×3=$72 to purchase new video games and is left with $120-$72=$48 to purchase used video games.

She can buy $48÷9=5.3 new ones. This can be rounded off to 5 new ones.