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Finding the Fourth Proportional to 520.61, 780.94 and 429.14

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Solution

The fourth proportional to 520.61, 780.94 and 429.14 is: 643.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.61 : 780.94 = 429.14 : x
  2. Step 2: Convert to fraction form
    520.61/780.94 = 429.14/x
  3. Step 3: Cross multiply
    520.61x = 780.94 × 429.14
  4. Step 4: Simplify right side
    520.61x = 335,134.53
  5. Step 5: Solve for x
    x = 335,134.53/520.61
  6. Step 6: Final answer
    x = 643.74

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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.