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Finding the Fourth Proportional to 328.72, 490.82 and 289.89

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Solution

The fourth proportional to 328.72, 490.82 and 289.89 is: 432.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.72 : 490.82 = 289.89 : x
  2. Step 2: Convert to fraction form
    328.72/490.82 = 289.89/x
  3. Step 3: Cross multiply
    328.72x = 490.82 × 289.89
  4. Step 4: Simplify right side
    328.72x = 142,284.31
  5. Step 5: Solve for x
    x = 142,284.31/328.72
  6. Step 6: Final answer
    x = 432.85

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.