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Finding the Fourth Proportional to 521.10, 781.64 and 155.85

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Solution

The fourth proportional to 521.10, 781.64 and 155.85 is: 233.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.10 : 781.64 = 155.85 : x
  2. Step 2: Convert to fraction form
    521.10/781.64 = 155.85/x
  3. Step 3: Cross multiply
    521.10x = 781.64 × 155.85
  4. Step 4: Simplify right side
    521.10x = 121,817.81
  5. Step 5: Solve for x
    x = 121,817.81/521.10
  6. Step 6: Final answer
    x = 233.77

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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.