NAME _______________________________________ DATE _________ PERIOD_______
Dear Parent or Guardian:
Today we began Chapter 1 Ratios and Proportional Reasoning. In this chapter, your student will identify proportional and nonproportional relationships. Also, we will be finding the slope of a line. Included in this letter are key vocabulary words and activities you can do with your student. If you have any questions or comments, feel free to contact me at school.
Sincerely,
Vocabulary constant rate of change The rate of change in a linear relationship. cross product The product of the numerator of one ratio and the denominator of the other ratio. The cross products of any proportion are equal. direct variation The relationship between two variable quantities that have a constant ratio. nonproportional The relationship between two ratios with a rate or ratio that is not constant. proportion An equation stating that two ratios or rates are equivalent. rate A ratio that compares two quantities with different kinds of units. slope The rate of change between any two points on a line. It is the ratio of vertical change to horizontal change. The slope tells how steep the line is. unit rate A rate that is simplified so that it has a denominator of 1 unit.
Course 2 · Chapter 1 Ratios and Proportional Reasoning

NAME
• Keep a record of the length of time you spend doing homework every day for a week.
• Make a table showing the number of the day and the number of hours.
• Graph your ordered pairs.
• Find the rate of change from Monday to
Friday. Is it a constant rate of change?
Is your graph that of a linear function?
DATE PERIOD
• Find a formula from science or mathematics, for example C
=
πd, which is a direct variation function.
• Find the constant of variation.
• Graph the function.
c d
Course 2 • Chapter 1 Ratios and Proportional Reasoning