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Finding the Fourth Proportional to 430.32, 645.10 and 257.16

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Solution

The fourth proportional to 430.32, 645.10 and 257.16 is: 385.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.32 : 645.10 = 257.16 : x
  2. Step 2: Convert to fraction form
    430.32/645.10 = 257.16/x
  3. Step 3: Cross multiply
    430.32x = 645.10 × 257.16
  4. Step 4: Simplify right side
    430.32x = 165,893.92
  5. Step 5: Solve for x
    x = 165,893.92/430.32
  6. Step 6: Final answer
    x = 385.51

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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.