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Finding the Fourth Proportional to 806.33, 1,209.78 and 319.71

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Solution

The fourth proportional to 806.33, 1,209.78 and 319.71 is: 479.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.33 : 1,209.78 = 319.71 : x
  2. Step 2: Convert to fraction form
    806.33/1,209.78 = 319.71/x
  3. Step 3: Cross multiply
    806.33x = 1,209.78 × 319.71
  4. Step 4: Simplify right side
    806.33x = 386,778.76
  5. Step 5: Solve for x
    x = 386,778.76/806.33
  6. Step 6: Final answer
    x = 479.68

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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.