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Finding the Fourth Proportional to 430.36, 645.32 and 257.08

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Solution

The fourth proportional to 430.36, 645.32 and 257.08 is: 385.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.36 : 645.32 = 257.08 : x
  2. Step 2: Convert to fraction form
    430.36/645.32 = 257.08/x
  3. Step 3: Cross multiply
    430.36x = 645.32 × 257.08
  4. Step 4: Simplify right side
    430.36x = 165,898.87
  5. Step 5: Solve for x
    x = 165,898.87/430.36
  6. Step 6: Final answer
    x = 385.49

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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.