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Finding the Fourth Proportional to 447.39, 669.60 and 390.33

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Solution

The fourth proportional to 447.39, 669.60 and 390.33 is: 584.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.39 : 669.60 = 390.33 : x
  2. Step 2: Convert to fraction form
    447.39/669.60 = 390.33/x
  3. Step 3: Cross multiply
    447.39x = 669.60 × 390.33
  4. Step 4: Simplify right side
    447.39x = 261,364.97
  5. Step 5: Solve for x
    x = 261,364.97/447.39
  6. Step 6: Final answer
    x = 584.20

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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.