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Finding the Fourth Proportional to 688.61, 950.30 and 408.85

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Solution

The fourth proportional to 688.61, 950.30 and 408.85 is: 564.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.61 : 950.30 = 408.85 : x
  2. Step 2: Convert to fraction form
    688.61/950.30 = 408.85/x
  3. Step 3: Cross multiply
    688.61x = 950.30 × 408.85
  4. Step 4: Simplify right side
    688.61x = 388,524.72
  5. Step 5: Solve for x
    x = 388,524.72/688.61
  6. Step 6: Final answer
    x = 564.22

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.