Question

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A company owns two dealerships, both of which sell cars and trucks. Dealership A sells a total of 164 cars and trucks. Dealership B sells twice as many cars and half as many trucks as Dealership A, and sells a total of 229 cars and trucks.

(4 points)
a) An equation for the total cars and trucks for Dealership A:

b) An equation for the total cars and trucks for Dealership B:

c) How many cars did Dealership A sell?

d) Considering that Dealership B sold half as many trucks as Dealership A, how many trucks did Dealership B sell?

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1 answer

To solve this problem, let's define our variables:

  • Let \( c_A \) be the number of cars sold by Dealership A.
  • Let \( t_A \) be the number of trucks sold by Dealership A.
  • Let \( c_B \) be the number of cars sold by Dealership B.
  • Let \( t_B \) be the number of trucks sold by Dealership B.

a) An equation for the total cars and trucks for Dealership A:

The total number of cars and trucks sold by Dealership A is given by: \[ c_A + t_A = 164 \]

b) An equation for the total cars and trucks for Dealership B:

According to the problem, Dealership B sells twice as many cars and half as many trucks as Dealership A. So, we can express it as follows:

  • Cars sold by Dealership B: \( c_B = 2c_A \)
  • Trucks sold by Dealership B: \( t_B = \frac{1}{2}t_A \)

The total for Dealership B is given by: \[ c_B + t_B = 229 \] Substituting the expressions for \( c_B \) and \( t_B \): \[ 2c_A + \frac{1}{2}t_A = 229 \]

c) How many cars did Dealership A sell?

Now we have the system of equations:

  1. \( c_A + t_A = 164 \) (Equation 1)
  2. \( 2c_A + \frac{1}{2}t_A = 229 \) (Equation 2)

We can solve these equations simultaneously.

From Equation 1: \[ t_A = 164 - c_A \]

Substitute \( t_A \) in Equation 2: \[ 2c_A + \frac{1}{2}(164 - c_A) = 229 \] Expanding this: \[ 2c_A + 82 - \frac{1}{2}c_A = 229 \] Simplifying the equation: \[ (2 - \frac{1}{2})c_A + 82 = 229 \] \[ \frac{3}{2}c_A = 229 - 82 \] \[ \frac{3}{2}c_A = 147 \] Multiplying both sides by \( \frac{2}{3} \): \[ c_A = \frac{2}{3} \cdot 147 = 98 \]

So, Dealership A sold 98 cars.

d) Considering that Dealership B sold half as many trucks as Dealership A, how many trucks did Dealership B sell?

Now that we know \( c_A = 98 \), we can find \( t_A \): \[ t_A = 164 - c_A = 164 - 98 = 66 \]

Next, we can find \( t_B \): Since Dealership B sold half as many trucks as Dealership A: \[ t_B = \frac{1}{2}t_A = \frac{1}{2} \cdot 66 = 33 \]

Thus, Dealership B sold 33 trucks.

Summary:

  • a) \( c_A + t_A = 164 \)
  • b) \( 2c_A + \frac{1}{2}t_A = 229 \)
  • c) Dealership A sold 98 cars.
  • d) Dealership B sold 33 trucks.