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Finding the Fourth Proportional to 430.04, 645.20 and 256.68

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Solution

The fourth proportional to 430.04, 645.20 and 256.68 is: 385.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.04 : 645.20 = 256.68 : x
  2. Step 2: Convert to fraction form
    430.04/645.20 = 256.68/x
  3. Step 3: Cross multiply
    430.04x = 645.20 × 256.68
  4. Step 4: Simplify right side
    430.04x = 165,609.94
  5. Step 5: Solve for x
    x = 165,609.94/430.04
  6. Step 6: Final answer
    x = 385.10

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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.