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Finding the Fourth Proportional to 709.30, 978.79 and 394.54

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Solution

The fourth proportional to 709.30, 978.79 and 394.54 is: 544.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    709.30 : 978.79 = 394.54 : x
  2. Step 2: Convert to fraction form
    709.30/978.79 = 394.54/x
  3. Step 3: Cross multiply
    709.30x = 978.79 × 394.54
  4. Step 4: Simplify right side
    709.30x = 386,171.81
  5. Step 5: Solve for x
    x = 386,171.81/709.30
  6. Step 6: Final answer
    x = 544.44

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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.