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Finding the Fourth Proportional to 645.22, 890.49 and 409.29

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Solution

The fourth proportional to 645.22, 890.49 and 409.29 is: 564.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.22 : 890.49 = 409.29 : x
  2. Step 2: Convert to fraction form
    645.22/890.49 = 409.29/x
  3. Step 3: Cross multiply
    645.22x = 890.49 × 409.29
  4. Step 4: Simplify right side
    645.22x = 364,468.65
  5. Step 5: Solve for x
    x = 364,468.65/645.22
  6. Step 6: Final answer
    x = 564.88

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.