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Finding the Fourth Proportional to 430.47, 645.06 and 214.20

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Solution

The fourth proportional to 430.47, 645.06 and 214.20 is: 320.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.47 : 645.06 = 214.20 : x
  2. Step 2: Convert to fraction form
    430.47/645.06 = 214.20/x
  3. Step 3: Cross multiply
    430.47x = 645.06 × 214.20
  4. Step 4: Simplify right side
    430.47x = 138,171.85
  5. Step 5: Solve for x
    x = 138,171.85/430.47
  6. Step 6: Final answer
    x = 320.98

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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.