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Finding the Fourth Proportional to 709.08, 978.94 and 447.20

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Solution

The fourth proportional to 709.08, 978.94 and 447.20 is: 617.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    709.08 : 978.94 = 447.20 : x
  2. Step 2: Convert to fraction form
    709.08/978.94 = 447.20/x
  3. Step 3: Cross multiply
    709.08x = 978.94 × 447.20
  4. Step 4: Simplify right side
    709.08x = 437,781.97
  5. Step 5: Solve for x
    x = 437,781.97/709.08
  6. Step 6: Final answer
    x = 617.39

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.