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Finding the Fourth Proportional to 709.80, 979.57 and 395.13

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Solution

The fourth proportional to 709.80, 979.57 and 395.13 is: 545.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    709.80 : 979.57 = 395.13 : x
  2. Step 2: Convert to fraction form
    709.80/979.57 = 395.13/x
  3. Step 3: Cross multiply
    709.80x = 979.57 × 395.13
  4. Step 4: Simplify right side
    709.80x = 387,057.49
  5. Step 5: Solve for x
    x = 387,057.49/709.80
  6. Step 6: Final answer
    x = 545.31

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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.