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Finding the Fourth Proportional to 470.19, 647.66 and 391.35

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Solution

The fourth proportional to 470.19, 647.66 and 391.35 is: 539.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    470.19 : 647.66 = 391.35 : x
  2. Step 2: Convert to fraction form
    470.19/647.66 = 391.35/x
  3. Step 3: Cross multiply
    470.19x = 647.66 × 391.35
  4. Step 4: Simplify right side
    470.19x = 253,459.78
  5. Step 5: Solve for x
    x = 253,459.78/470.19
  6. Step 6: Final answer
    x = 539.06

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.