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Finding the Fourth Proportional to 521.12, 781.85 and 155.91

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Solution

The fourth proportional to 521.12, 781.85 and 155.91 is: 233.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.12 : 781.85 = 155.91 : x
  2. Step 2: Convert to fraction form
    521.12/781.85 = 155.91/x
  3. Step 3: Cross multiply
    521.12x = 781.85 × 155.91
  4. Step 4: Simplify right side
    521.12x = 121,897.98
  5. Step 5: Solve for x
    x = 121,897.98/521.12
  6. Step 6: Final answer
    x = 233.91

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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.