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Finding the Fourth Proportional to 800.72, 1,201.08 and 389.60

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Solution

The fourth proportional to 800.72, 1,201.08 and 389.60 is: 584.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.72 : 1,201.08 = 389.60 : x
  2. Step 2: Convert to fraction form
    800.72/1,201.08 = 389.60/x
  3. Step 3: Cross multiply
    800.72x = 1,201.08 × 389.60
  4. Step 4: Simplify right side
    800.72x = 467,940.77
  5. Step 5: Solve for x
    x = 467,940.77/800.72
  6. Step 6: Final answer
    x = 584.40

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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.