Finding the Fourth Proportional to 86.20, 129.11 and 68.99
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Solution
The fourth proportional to 86.20, 129.11 and 68.99 is: 103.33
Step by Step Solution
- Step 1: Write the proportion equation
86.20 : 129.11 = 68.99 : x - Step 2: Convert to fraction form
86.20/129.11 = 68.99/x - Step 3: Cross multiply
86.20x = 129.11 × 68.99 - Step 4: Simplify right side
86.20x = 8,906.83 - Step 5: Solve for x
x = 8,906.83/86.20 - Step 6: Final answer
x = 103.33
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.