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Finding the Fourth Proportional to 430.00, 645.37 and 339.28

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Solution

The fourth proportional to 430.00, 645.37 and 339.28 is: 509.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.00 : 645.37 = 339.28 : x
  2. Step 2: Convert to fraction form
    430.00/645.37 = 339.28/x
  3. Step 3: Cross multiply
    430.00x = 645.37 × 339.28
  4. Step 4: Simplify right side
    430.00x = 218,958.67
  5. Step 5: Solve for x
    x = 218,958.67/430.00
  6. Step 6: Final answer
    x = 509.21

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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.