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Finding the Fourth Proportional to 638.28, 954.09 and 555.39

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Solution

The fourth proportional to 638.28, 954.09 and 555.39 is: 830.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.28 : 954.09 = 555.39 : x
  2. Step 2: Convert to fraction form
    638.28/954.09 = 555.39/x
  3. Step 3: Cross multiply
    638.28x = 954.09 × 555.39
  4. Step 4: Simplify right side
    638.28x = 529,892.05
  5. Step 5: Solve for x
    x = 529,892.05/638.28
  6. Step 6: Final answer
    x = 830.19

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.