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Finding the Fourth Proportional to 520.34, 780.10 and 289.31

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Solution

The fourth proportional to 520.34, 780.10 and 289.31 is: 433.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.34 : 780.10 = 289.31 : x
  2. Step 2: Convert to fraction form
    520.34/780.10 = 289.31/x
  3. Step 3: Cross multiply
    520.34x = 780.10 × 289.31
  4. Step 4: Simplify right side
    520.34x = 225,690.73
  5. Step 5: Solve for x
    x = 225,690.73/520.34
  6. Step 6: Final answer
    x = 433.74

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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.