CA Foundation · Quantitative Aptitude · Equations
A firm's total revenue is R = 50x − x² and total cost is C = 10x + 200, where x is units sold. What is the largest number of units at which the firm just breaks even?
Breaking even requires 50x − x² = 10x + 200, giving x² − 40x + 200 = 0, whose roots are not whole numbers, so this question is flawed.
- A10
- B20Correct
- C30
- D40
Explanation
Break-even needs R = C: 50x − x² = 10x + 200, so x² − 40x + 200 = 0. Roots are x = 20 ± √200, which is not a whole number, so the data fails; hence no option fits.
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