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Finding the Fourth Proportional to 638.65, 960.18 and 517.78

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Solution

The fourth proportional to 638.65, 960.18 and 517.78 is: 778.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.65 : 960.18 = 517.78 : x
  2. Step 2: Convert to fraction form
    638.65/960.18 = 517.78/x
  3. Step 3: Cross multiply
    638.65x = 960.18 × 517.78
  4. Step 4: Simplify right side
    638.65x = 497,162.00
  5. Step 5: Solve for x
    x = 497,162.00/638.65
  6. Step 6: Final answer
    x = 778.46

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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.