Let’s solve this step by step.
We are told:
- Profit per DVD player = $125 → let x = number of DVD players sold
- Profit per CD player = $100 → let y = number of CD players sold
- Goal: total profit ≥ $500
So the inequality is:
125x + 100y ≥ 500
Now, we’re told the store sells
only 2 DVD players, so plug in x = 2:
→ 125(2) + 100y ≥ 500
→ 250 + 100y ≥ 500
Subtract 250 from both sides:
→ 100y ≥ 250
Divide both sides by 100:
→ y ≥ 2.5
But you can’t sell half a CD player — you have to sell whole units. So if y must be at least 2.5, then the smallest whole number that works is
3.
Check: If they sell 2 DVD players and 3 CD players:
Profit = 125×2 + 100×3 = 250 + 300 =
$550 → which is ≥ $500
✔
If they sold only 2 CD players:
Profit = 250 + 200 = $450 → too low
✘
So yes, they need to sell
at least 3 CD players.
Final Answer:
The store must sell at least 3 CD players.
Parent Tip: Review the logic above to help your child master the concept of systems of linear inequalities word problems worksheet.