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Finding the Fourth Proportional to 521.13, 780.98 and 289.68

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Solution

The fourth proportional to 521.13, 780.98 and 289.68 is: 434.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.13 : 780.98 = 289.68 : x
  2. Step 2: Convert to fraction form
    521.13/780.98 = 289.68/x
  3. Step 3: Cross multiply
    521.13x = 780.98 × 289.68
  4. Step 4: Simplify right side
    521.13x = 226,229.91
  5. Step 5: Solve for x
    x = 226,229.91/521.13
  6. Step 6: Final answer
    x = 434.11

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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.