Question

Justine charges $25 to wash a dog. She washed 5 dogs on Saturday and then some more on Sunday. She made $325 for the weekend. How many dogs did she wash on Sunday?Choose two answers: one for the equation that models this situation, and one for the correct answer.

Answer 1

Answer

• A. Equation: 25(5 + x) = 325

,

• B. Answer: 8 dogs

Explanation

Given

• Charge to wash a dog: $25.

• She washed 5 dogs on Saturday and then some more on Sunday.

• She made $325 for the weekend.

Procedure

She charges $25 per wash, she made $325 for the weekend, and we know that on Saturday she washed 5 dogs, but we don't know how many she washed on Sunday. Thus, we have to build an equation in which the number of dogs washed on Sunday is represented by x (as we do not know the real number).

Considering that the total money made has to be equal to the multiplication of the charge times the dogs washed, the equation is:

$25(5+x)=325$

Then, we have to solve for x to know how many dogs did she wash on Sunday.

0. Multiplying the parenthesis

$125+25x=325$

2. Subtracting 125 from both sides of the equation

$125-125+25x=325-125$$25x=200$

3. Dividing both sides of the equation against 25

$\frac{25x}{25}=\frac{200}{25}$$x=8$