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Finding the Fourth Proportional to 520.72, 780.47 and 325.20

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Solution

The fourth proportional to 520.72, 780.47 and 325.20 is: 487.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.72 : 780.47 = 325.20 : x
  2. Step 2: Convert to fraction form
    520.72/780.47 = 325.20/x
  3. Step 3: Cross multiply
    520.72x = 780.47 × 325.20
  4. Step 4: Simplify right side
    520.72x = 253,808.84
  5. Step 5: Solve for x
    x = 253,808.84/520.72
  6. Step 6: Final answer
    x = 487.42

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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.