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Finding the Fourth Proportional to 807.39, 1,209.37 and 390.29

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Solution

The fourth proportional to 807.39, 1,209.37 and 390.29 is: 584.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.39 : 1,209.37 = 390.29 : x
  2. Step 2: Convert to fraction form
    807.39/1,209.37 = 390.29/x
  3. Step 3: Cross multiply
    807.39x = 1,209.37 × 390.29
  4. Step 4: Simplify right side
    807.39x = 472,008.38
  5. Step 5: Solve for x
    x = 472,008.38/807.39
  6. Step 6: Final answer
    x = 584.61

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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.