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Finding the Fourth Proportional to 521.56, 780.81 and 487.36

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Solution

The fourth proportional to 521.56, 780.81 and 487.36 is: 729.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.56 : 780.81 = 487.36 : x
  2. Step 2: Convert to fraction form
    521.56/780.81 = 487.36/x
  3. Step 3: Cross multiply
    521.56x = 780.81 × 487.36
  4. Step 4: Simplify right side
    521.56x = 380,535.56
  5. Step 5: Solve for x
    x = 380,535.56/521.56
  6. Step 6: Final answer
    x = 729.61

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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.