1. Understanding Proportions
LESSON 7-3
Additional Examples
Do the ratios in each pair form a proportion?
a , 42 77 6 14 3 13 9 39
b ,
 7
 3 42 77 6 14 3 13 9 39
14  7 = 98, not 77
Compare ratios. 42 77 6 14 = /
Compare ratios. 3 13 9 39 =
and do not form a proportion. 42 77 6 14
and form a proportion. 3 13 9 39

2. Understanding Proportions
LESSON 7-3
Additional Examples
In one class, 2 out of 16 students’ favorite
subject is math. In another class, 4 out of 12 students’
favorite subject is math. Are these ratios equal? Write
ratios for each class.
4 math students
12 total students
2 math students
16 total students
4 ÷ 4
12 ÷ 4 1 3 8
Simplify.
2 ÷ 2
16÷ 2
The ratios are not equal. 3 1 8