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Finding the Fourth Proportional to 619.19, 930.71 and 389.55

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Solution

The fourth proportional to 619.19, 930.71 and 389.55 is: 585.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.19 : 930.71 = 389.55 : x
  2. Step 2: Convert to fraction form
    619.19/930.71 = 389.55/x
  3. Step 3: Cross multiply
    619.19x = 930.71 × 389.55
  4. Step 4: Simplify right side
    619.19x = 362,560.35
  5. Step 5: Solve for x
    x = 362,560.35/619.19
  6. Step 6: Final answer
    x = 585.54

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.