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Finding the Fourth Proportional to 619.36, 855.30 and 398.62

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Solution

The fourth proportional to 619.36, 855.30 and 398.62 is: 550.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.36 : 855.30 = 398.62 : x
  2. Step 2: Convert to fraction form
    619.36/855.30 = 398.62/x
  3. Step 3: Cross multiply
    619.36x = 855.30 × 398.62
  4. Step 4: Simplify right side
    619.36x = 340,939.69
  5. Step 5: Solve for x
    x = 340,939.69/619.36
  6. Step 6: Final answer
    x = 550.47

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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.