Last week Jacob had $30. He washed cars over the weekend and earned $15 for every car he washed. If he now has $105, how many cars did he wash?

Question

Choose the correct equation to solve the problem and the answer. (4 point)
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4 points
30 - 15x = 105 and x = -5 cars
30 + 15x = 105 and x = 5 cars
105 + x = 30 and x = 75 dollars
(6.) How many books can you buy with 255 dollars if each book cost $17?
Choose the correct equation to solve the problem and the answer. (4 point)
*
4 points
255 - 17 = x and x = 272 books
17x = 255 and x = 15 books
17 - x = 255 and x = 238 books

Answer 1

Let's solve the two problems one by one.

1. Jacob's Car Washing Problem:
   • Jacob started with $30 and earned $15 for each car he washed.
   • He now has $105.

To find the number of cars he washed, we can set up the equation as follows:

\[ 30 + 15x = 105 \]

Where \(x\) is the number of cars washed.

Now, let's solve for \(x\):

\[ 15x = 105 - 30 \] \[ 15x = 75 \] \[ x = 5 \]

So, the correct equation is \(30 + 15x = 105\) and \(x = 5\) cars.

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2. Book Buying Problem:
   • You have $255 and each book costs $17.

To find out how many books you can buy, we can set up the equation:

\[ 17x = 255 \]

Where \(x\) is the number of books.

Now, let's solve for \(x\):

\[ x = \frac{255}{17} \] \[ x = 15 \]

So, the correct equation is \(17x = 255\) and \(x = 15\) books.

In summary:

1. For Jacob, the correct equation is \(30 + 15x = 105\) and \(x = 5\) cars.
2. For buying books, the correct equation is \(17x = 255\) and \(x = 15\) books.