Transcript Solving Proportions - Grays Harbor College

Solving Proportions
Section 5.2
Objectives
• Determine whether a proportion is true or
false
• Solve a proportion
Objective 1:
Determine whether a proportion
is true or false
Objective 1
• Proportions states two ratios are equal
• Cross multiplication – checks whether
proportion is true or false
– Cross multiplication is shortcut for converting
both fractions to have common denominator
and checking that numerators match
Objective 1
• To check whether proportion is true or
false
– Check that ratios or rates have same units
– Cross multiply
– If cross products are equal, proportion is true
Objective 2:
Solve a proportion
Objective 2
• If three numbers of proportion are given,
you can find the fourth
• To solve a proportion
– Cross multiply
– Do related division to find missing number