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Finding the Fourth Proportional to 619.39, 855.11 and 409.50

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Solution

The fourth proportional to 619.39, 855.11 and 409.50 is: 565.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.39 : 855.11 = 409.50 : x
  2. Step 2: Convert to fraction form
    619.39/855.11 = 409.50/x
  3. Step 3: Cross multiply
    619.39x = 855.11 × 409.50
  4. Step 4: Simplify right side
    619.39x = 350,165.50
  5. Step 5: Solve for x
    x = 350,165.50/619.39
  6. Step 6: Final answer
    x = 565.34

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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.