Finding the Third Proportional to 118 and 128.50
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Solution
The third proportional to 118 and 128.50 is: 139.93
Step by Step Solution
- Step 1: Write the proportion equation
118 : 128.50 = 128.50 : x - Step 2: Convert to fraction form
118/128.50 = 128.50/x - Step 3: Cross multiply
118x = 128.50 × 128.50 - Step 4: Simplify right side
118x = 16,512.25 - Step 5: Solve for x
x = 16,512.25/118 - Step 6: Final answer
x = 139.93
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These problems maintain the same ratio (1.09) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.