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Finding the Fourth Proportional to 709.07, 978.45 and 394.31

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Solution

The fourth proportional to 709.07, 978.45 and 394.31 is: 544.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    709.07 : 978.45 = 394.31 : x
  2. Step 2: Convert to fraction form
    709.07/978.45 = 394.31/x
  3. Step 3: Cross multiply
    709.07x = 978.45 × 394.31
  4. Step 4: Simplify right side
    709.07x = 385,807.73
  5. Step 5: Solve for x
    x = 385,807.73/709.07
  6. Step 6: Final answer
    x = 544.11

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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.