π Question 1
Math
Real Numbers
β 4 Marks
π Case Study
Real-life Application: Cost optimization using quadratic equations.
Q. A shopkeeper buys a certain number of books for βΉ960. If he had bought 4 more books for the same amount, each book would have cost βΉ8 less. Find the number of books bought.
β
Detailed Solution
Let x = number of books
Cost per book = 960/x
Given: 960/x - 960/(x+4) = 8
960(x+4) - 960x = 8x(x+4)
3840 = 8xΒ² + 32x
xΒ² + 4x - 480 = 0
(x+24)(x-20) = 0
x = 20 books β
π Learning Outcomes
- Form quadratic equations
- Apply algebra to real-life
- Solve word problems