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Finding the Fourth Proportional to 800.05, 1,200.38 and 389.16

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Solution

The fourth proportional to 800.05, 1,200.38 and 389.16 is: 583.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.05 : 1,200.38 = 389.16 : x
  2. Step 2: Convert to fraction form
    800.05/1,200.38 = 389.16/x
  3. Step 3: Cross multiply
    800.05x = 1,200.38 × 389.16
  4. Step 4: Simplify right side
    800.05x = 467,139.88
  5. Step 5: Solve for x
    x = 467,139.88/800.05
  6. Step 6: Final answer
    x = 583.89

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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.