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Finding the Fourth Proportional to 430.57, 645.90 and 214.09

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Solution

The fourth proportional to 430.57, 645.90 and 214.09 is: 321.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.57 : 645.90 = 214.09 : x
  2. Step 2: Convert to fraction form
    430.57/645.90 = 214.09/x
  3. Step 3: Cross multiply
    430.57x = 645.90 × 214.09
  4. Step 4: Simplify right side
    430.57x = 138,280.73
  5. Step 5: Solve for x
    x = 138,280.73/430.57
  6. Step 6: Final answer
    x = 321.16

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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.