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Finding the Fourth Proportional to 505.10, 756.09 and 431.30

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Solution

The fourth proportional to 505.10, 756.09 and 431.30 is: 645.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.10 : 756.09 = 431.30 : x
  2. Step 2: Convert to fraction form
    505.10/756.09 = 431.30/x
  3. Step 3: Cross multiply
    505.10x = 756.09 × 431.30
  4. Step 4: Simplify right side
    505.10x = 326,097.57
  5. Step 5: Solve for x
    x = 326,097.57/505.10
  6. Step 6: Final answer
    x = 645.61

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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.