Objective: To test whether ratios form a proportion by using equivalent ratios and cross products.
5-3 Proportions (p. 193 )
A proportion is a statement that states two ratios are equal.
Cross products are two products found by multiplying the
denominator of each ratio by the numerator of the other ratio.
If two ratios have equal cross products, they form a proportion.
6 ? 9
8 = 12
Objective: To test whether ratios form a proportion by using equivalent ratios and cross products.
EX 1: Do the ratios form a proportion? Show your work.
a) 42 =? 56
56 64
b) 4 =? 6
10 15
c) 8 =? 9
6
7
Objective: To test whether ratios form a proportion by using equivalent ratios and cross products.
EX 2: Refer to the table. For each class, write
the ratio of the number of students who saw a
movie to the total number of students. Do the
ratios form a proportion?