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Finding the Fourth Proportional to 619.81, 855.20 and 371.09

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Solution

The fourth proportional to 619.81, 855.20 and 371.09 is: 512.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.81 : 855.20 = 371.09 : x
  2. Step 2: Convert to fraction form
    619.81/855.20 = 371.09/x
  3. Step 3: Cross multiply
    619.81x = 855.20 × 371.09
  4. Step 4: Simplify right side
    619.81x = 317,354.31
  5. Step 5: Solve for x
    x = 317,354.31/619.81
  6. Step 6: Final answer
    x = 512.02

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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.