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Finding the Fourth Proportional to 618.90, 925.65 and 521.70

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Solution

The fourth proportional to 618.90, 925.65 and 521.70 is: 780.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.90 : 925.65 = 521.70 : x
  2. Step 2: Convert to fraction form
    618.90/925.65 = 521.70/x
  3. Step 3: Cross multiply
    618.90x = 925.65 × 521.70
  4. Step 4: Simplify right side
    618.90x = 482,911.61
  5. Step 5: Solve for x
    x = 482,911.61/618.90
  6. Step 6: Final answer
    x = 780.27

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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.