A charging station can only charge cell phones and laptops. Cell phones use approximately 3 joules per second (sJ) when charging, and laptops use approximately 40sJ when charging. Which of the following equations represents the relationship between the number of cell phones, c, and the number of laptops, l, that could be charging when the station's output is exactly 160sJ ?Choose 1 answer:(A) c=−40l+160(B) c=−340l+3160(C) c=−3l+160(D) c=−403l+40160
Q. A charging station can only charge cell phones and laptops. Cell phones use approximately 3 joules per second (sJ) when charging, and laptops use approximately 40sJ when charging. Which of the following equations represents the relationship between the number of cell phones, c, and the number of laptops, l, that could be charging when the station's output is exactly 160sJ ?Choose 1 answer:(A) c=−40l+160(B) c=−340l+3160(C) c=−3l+160(D) c=−403l+40160
Define Total Power: Let's denote the total power used by cell phones as Pc and the total power used by laptops as Pl. The power used by cell phones is 3 joules per second per cell phone, and the power used by laptops is 40 joules per second per laptop. The total power output of the station is 160 joules per second. We can write the equation representing the total power output as:Pc+Pl=160Substituting the power usage for cell phones and laptops, we get:3c+40l=160
Equation Representation: We need to express c in terms of l. To do this, we will isolate c on one side of the equation. We can subtract 40l from both sides to get:3c=160−40l
Isolate c: Now, we divide both sides of the equation by 3 to solve for c:c=3160−40l
Solve for c: We can simplify the equation by distributing the division across the terms in the numerator: c=3160−340l
Final Simplification: The equation c=3160−340l matches one of the given choices, which is:(B) \(c = -\left(\frac{\(40\)}{\(3\)}\right)l + \left(\frac{\(160\)}{\(3\)}\right)
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