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Finding the Fourth Proportional to 669.40, 1,004.10 and 439.75

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Solution

The fourth proportional to 669.40, 1,004.10 and 439.75 is: 659.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.40 : 1,004.10 = 439.75 : x
  2. Step 2: Convert to fraction form
    669.40/1,004.10 = 439.75/x
  3. Step 3: Cross multiply
    669.40x = 1,004.10 × 439.75
  4. Step 4: Simplify right side
    669.40x = 441,552.98
  5. Step 5: Solve for x
    x = 441,552.98/669.40
  6. Step 6: Final answer
    x = 659.63

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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.