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Set 17: Linear Inequalities (Advanced)

Explanation

Answer: A

A company needs at least 100 units of X and 200 units of Y. Machine A produces 10X and 5Y per hour. Machine B produces 5X and 10Y per hour. Minimize hours (hA+hBh_A + h_B). Which constraints apply?

A.

10A+5B100,5A+10B200,A,B010A + 5B \geq 100, 5A + 10B \geq 200, A,B \geq 0

✓ Correct
B.

10A+5B100,5A+10B200,A,B010A + 5B \leq 100, 5A + 10B \leq 200, A,B \geq 0

C.

10A+5B200,5A+10B100,A,B010A + 5B \geq 200, 5A + 10B \geq 100, A,B \geq 0

D.

A+B300,A,B0A + B \geq 300, A,B \geq 0

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Production constraints. 1. Product X: 10A+5B10010A + 5 B \geq 100 2. Product Y: 5A+10B2005A + 10 B \geq 200 3. Non-negativity: A,B0A, B \geq 0 Strategic Tip: Ensure the coefficients match the machine output rates for each product. Choice B is incorrect because it sets maximum limits instead of minimum requirements. Choice C is incorrect because it swaps the requirements for X and Y. Choice D is incorrect because it sums the units directly.

Key Steps:

The correct answer is 10A+5B100,5A+10B200,A,B010A + 5B \geq 100, 5A + 10B \geq 200, A,B \geq 0

Why others are wrong:
B: Choice B is incorrect and may result from a calculation error.
C: Choice C is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

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