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Finding the Fourth Proportional to 665.35, 997.08 and 520.90

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Solution

The fourth proportional to 665.35, 997.08 and 520.90 is: 780.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.35 : 997.08 = 520.90 : x
  2. Step 2: Convert to fraction form
    665.35/997.08 = 520.90/x
  3. Step 3: Cross multiply
    665.35x = 997.08 × 520.90
  4. Step 4: Simplify right side
    665.35x = 519,378.97
  5. Step 5: Solve for x
    x = 519,378.97/665.35
  6. Step 6: Final answer
    x = 780.61

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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.