AlgebraMediumInequality from a budget
Algebra practice question
Priya has $50 to spend on notebooks that cost $6 each. The order also has a single shipping charge of $8, regardless of how many notebooks she buys.
What is the greatest number of notebooks Priya can buy?
Answer: 7
Let n be the number of notebooks. The total cost is 6n + 8, which must stay within the budget: 6n + 8 ≤ 50. Subtract 8: 6n ≤ 42. Divide by 6: n ≤ 7. Since she can only buy whole notebooks, the greatest number is 7. Check: 6(7) + 8 = 50, exactly the budget.
Common wrong answers
- If you answered 8
- That ignores the $8 shipping: 50/6 = 8.33, rounded down to 8. But 8 notebooks plus shipping costs $56, over budget.
- If you answered 9
- That adds the shipping to the budget instead of subtracting it: (50 + 8)/6 = 9.67. Shipping is a cost that comes OUT of the $50.
- If you answered 42
- 42 is the amount left for notebooks after shipping, in dollars — not the number of notebooks. Divide by the $6 price.
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