5-3 Proportions Lesson Link: Tell if each pair of ratios are equivalent. Write yes or no and explain. a.) b.) c.) d.)

Create two different proportions using = = A proportion is a statement that shows two ratios are equal, or proportional. Proportions can be written in numbers or in words. "One is to two as three is to six."

First Method: Rewrite the ratios in lowest terms and see if they are equivalent. 1.) = = 2.) Decide if and are proportional = =

Second Method: Use related multiplication to test proportionality 1.) 2.)

Third Method: Use cross products (diagonal multiplication) to test proportionality 1.) 2.)

Real-life problem: Researchers tracking a pod (group) of killer whales found that the whales swam 30 miles in 4 hours on Monday and 64 miles in 8 hours on Tuesday. Are these rates proportional? Use all three methods to test proportionality. lowest terms related multiplication cross products

Demonstrate Understanding: Determine whether the ratios form a proportion. You may use a calculator, but must show work. 1.) 2.) 3.) 4.) 5.) 6.)