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Finding the Fourth Proportional to 447.45, 669.60 and 390.30

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Solution

The fourth proportional to 447.45, 669.60 and 390.30 is: 584.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.45 : 669.60 = 390.30 : x
  2. Step 2: Convert to fraction form
    447.45/669.60 = 390.30/x
  3. Step 3: Cross multiply
    447.45x = 669.60 × 390.30
  4. Step 4: Simplify right side
    447.45x = 261,344.88
  5. Step 5: Solve for x
    x = 261,344.88/447.45
  6. Step 6: Final answer
    x = 584.08

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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.