Mrs Chang knows knows that she spends $180 for groceries each week for her family. If this is 12% of the family's total income for the week, how much do they earn each week?

Set up a percent equation and solve

Let x be the family's total income for the week.

We know that 12% of x is equal to $180.
So 12% of x is (12/100)x = 0.12x.
Therefore, 0.12x = $180.
To find x, divide both sides of the equation by 0.12: x = $180/0.12 = $1500.
Therefore, the family earns $1500 each week. Answer: \boxed{1500}.

To set up a percent equation, let's start by assigning variables:

Let "x" be the total income for the week.

We know that Mrs Chang spends 12% of the family's total income on groceries, which is $180.
So, we can set up the equation:

12% of x = $180

To solve this equation, we need to convert 12% to decimal form.

12% = 12/100 = 0.12

Now, we can rewrite the equation:

0.12x = $180

To find the value of x, we can divide both sides of the equation by 0.12:

x = $180 / 0.12

x ≈ $1500

Therefore, the family earns approximately $1500 each week.

To solve this question, we need to set up a percent equation and solve for the total income of Mrs Chang's family.

Let's start by setting up the percent equation. We know that Mrs Chang spends $180 for groceries each week, which represents 12% of the family's total income for the week.

So, we can set up the equation as follows:

12% of the total income = $180.

To solve for the total income, we need to convert 12% to decimal form. Divide 12 by 100 to get 0.12:

0.12 (total income) = $180.

Now, we can solve for the total income by dividing both sides of the equation by 0.12:

total income = $180 / 0.12.

Using a calculator, we can divide $180 by 0.12 to find that the total income is $1500.

Therefore, Mrs Chang's family earns $1500 each week.