Family Worksheet for Pre-Algebra 7 and Pre-Algebra I

Percents and Percent of Change

Name ______

1. One of the clearest indicators of a poor society is that they spend a large proportion (percentage) of their income on basic necessities. Let’s compare your family with the typical American family and the typical Haitian family.

a. Find the percentage of your net income that you spend on housing and food.

Housing: ______%Food: ______%

b. In 1997, the average US household spent 10.7% of their income on food. How does that compare to your family? (source:

c. In 2007, the average US household spent 22.9% of their income on their house. How does that compare to your family? (source: 2008 World Almanach)

d. In 1988, the average Indian household spent 51.3% of their income on food. Does this mean that they spent more money on food than an American household? Are they spending more money than your family? If not, then how can their percentage be higher? (explain this using complete sentences) Source --

2. It’s common for many jobs to give a “cost-of-living raise” to their employees. This raise is not based on your performance, but is just given to people because the amount $1 is worth goes down a little bit every year. So, imagine that you get a cost-of-living increase this year of 3% of your salary.

That means that you have a 3% increase in your net income.

Find what your new monthly net income would be! (show your work!)______

3. Your tax rate is really a percent decrease of your income! To find out what rate you are being taxed at (approximately), you need to determine the percent decrease between your gross income and your net income. Find your paycheck. It should have a gross monthly income figure. Then, find your net monthly income. Using the method we learned in class, find what percent of change (i.e. what percent decrease) you have between your gross income (original amount) and net income (new amount):

Amount I pay in taxes each month: $______

My tax rate: ______%

4. Percents don’t work the way you think they should! Take for instance a sale at a retail store. Work through the following examples to see if you can see what I mean:

a. Find the new price of a $45 pair of jeans after a 20% off sale.

b. Now, say you had a coupon that let you get 10% off of the sale price. What would the new price be?

c. Is the new price the same as 30% off the original price (i.e. 20% off plus 10% off)? If not, is it higher or lower than 30% off? Why would this be?