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Finding the Fourth Proportional to 801.87, 1,201.83 and 390.39

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Solution

The fourth proportional to 801.87, 1,201.83 and 390.39 is: 585.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    801.87 : 1,201.83 = 390.39 : x
  2. Step 2: Convert to fraction form
    801.87/1,201.83 = 390.39/x
  3. Step 3: Cross multiply
    801.87x = 1,201.83 × 390.39
  4. Step 4: Simplify right side
    801.87x = 469,182.41
  5. Step 5: Solve for x
    x = 469,182.41/801.87
  6. Step 6: Final answer
    x = 585.11

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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.