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Finding the Fourth Proportional to 550.40, 824.68 and 387.28

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Solution

The fourth proportional to 550.40, 824.68 and 387.28 is: 580.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    550.40 : 824.68 = 387.28 : x
  2. Step 2: Convert to fraction form
    550.40/824.68 = 387.28/x
  3. Step 3: Cross multiply
    550.40x = 824.68 × 387.28
  4. Step 4: Simplify right side
    550.40x = 319,383.59
  5. Step 5: Solve for x
    x = 319,383.59/550.40
  6. Step 6: Final answer
    x = 580.28

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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.