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# A food truck sells salads for $6.50 each and drinks for$2.00 each. The food tru...

A food truck sells salads for $6.50 each and drinks for$2.00 each. The food truck’s revenue from selling a total of 209 salads and drinks in one day was $836.50. How many salads were sold that day? ### Options A) 77 B) 93 C) 99 D) 105 The correct answer is B. ### Explanation: Choice B is correct. To determine the number of salads sold, write and solve a system of two equations. Let x equal the number of salads sold and let y equal the number of drinks sold. Since a total of 209 salads and drinks were sold, the equation x + y = 209 must hold. Since salads cost$6.50 each, drinks cost $2.00 each, and the total revenue from selling x salads and y drinks was$836.50, the equation 6.50x + 2.00y = 836.50 must also hold. The equation x + y = 209 is equivalent to 2x + 2y = 418, and subtracting (2x + 2y) from the left-hand side and subtracting 418 from the right-hand side of 6.50x + 2.00y = 836.50 gives 4.5x = 418.50. Therefore, the number of salads sold, x, was $$x = \frac{418.50}{4.50} = 93$$.
Choices A, C, and D are incorrect and could result from errors in writing the equations and solving the system of equations. For example, choice C could have been obtained by dividing the total revenue, $836.50, by the total price of a salad and a drink,$8.50, and then rounding up.