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Finding the Fourth Proportional to 521.09, 781.76 and 155.87

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Solution

The fourth proportional to 521.09, 781.76 and 155.87 is: 233.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.09 : 781.76 = 155.87 : x
  2. Step 2: Convert to fraction form
    521.09/781.76 = 155.87/x
  3. Step 3: Cross multiply
    521.09x = 781.76 × 155.87
  4. Step 4: Simplify right side
    521.09x = 121,854.69
  5. Step 5: Solve for x
    x = 121,854.69/521.09
  6. Step 6: Final answer
    x = 233.85

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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.