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Finding the Fourth Proportional to 509.72, 764.41 and 217.21

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Solution

The fourth proportional to 509.72, 764.41 and 217.21 is: 325.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.72 : 764.41 = 217.21 : x
  2. Step 2: Convert to fraction form
    509.72/764.41 = 217.21/x
  3. Step 3: Cross multiply
    509.72x = 764.41 × 217.21
  4. Step 4: Simplify right side
    509.72x = 166,037.50
  5. Step 5: Solve for x
    x = 166,037.50/509.72
  6. Step 6: Final answer
    x = 325.75

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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.