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Finding the Fourth Proportional to 520.56, 780.81 and 289.56

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Solution

The fourth proportional to 520.56, 780.81 and 289.56 is: 434.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.56 : 780.81 = 289.56 : x
  2. Step 2: Convert to fraction form
    520.56/780.81 = 289.56/x
  3. Step 3: Cross multiply
    520.56x = 780.81 × 289.56
  4. Step 4: Simplify right side
    520.56x = 226,091.34
  5. Step 5: Solve for x
    x = 226,091.34/520.56
  6. Step 6: Final answer
    x = 434.32

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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.