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Finding the Fourth Proportional to 470.38, 648.18 and 420.50

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Solution

The fourth proportional to 470.38, 648.18 and 420.50 is: 579.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    470.38 : 648.18 = 420.50 : x
  2. Step 2: Convert to fraction form
    470.38/648.18 = 420.50/x
  3. Step 3: Cross multiply
    470.38x = 648.18 × 420.50
  4. Step 4: Simplify right side
    470.38x = 272,559.69
  5. Step 5: Solve for x
    x = 272,559.69/470.38
  6. Step 6: Final answer
    x = 579.45

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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.