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Finding the Fourth Proportional to 430.60, 645.02 and 213.56

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Solution

The fourth proportional to 430.60, 645.02 and 213.56 is: 319.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.60 : 645.02 = 213.56 : x
  2. Step 2: Convert to fraction form
    430.60/645.02 = 213.56/x
  3. Step 3: Cross multiply
    430.60x = 645.02 × 213.56
  4. Step 4: Simplify right side
    430.60x = 137,750.47
  5. Step 5: Solve for x
    x = 137,750.47/430.60
  6. Step 6: Final answer
    x = 319.90

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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.