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Finding the Fourth Proportional to 709.20, 978.54 and 447.12

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Solution

The fourth proportional to 709.20, 978.54 and 447.12 is: 616.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    709.20 : 978.54 = 447.12 : x
  2. Step 2: Convert to fraction form
    709.20/978.54 = 447.12/x
  3. Step 3: Cross multiply
    709.20x = 978.54 × 447.12
  4. Step 4: Simplify right side
    709.20x = 437,524.80
  5. Step 5: Solve for x
    x = 437,524.80/709.20
  6. Step 6: Final answer
    x = 616.93

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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.