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Finding the Fourth Proportional to 430.38, 645.29 and 257.08

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Solution

The fourth proportional to 430.38, 645.29 and 257.08 is: 385.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.38 : 645.29 = 257.08 : x
  2. Step 2: Convert to fraction form
    430.38/645.29 = 257.08/x
  3. Step 3: Cross multiply
    430.38x = 645.29 × 257.08
  4. Step 4: Simplify right side
    430.38x = 165,887.93
  5. Step 5: Solve for x
    x = 165,887.93/430.38
  6. Step 6: Final answer
    x = 385.45

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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.