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Finding the Fourth Proportional to 709.87, 979.62 and 399.37

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Solution

The fourth proportional to 709.87, 979.62 and 399.37 is: 551.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    709.87 : 979.62 = 399.37 : x
  2. Step 2: Convert to fraction form
    709.87/979.62 = 399.37/x
  3. Step 3: Cross multiply
    709.87x = 979.62 × 399.37
  4. Step 4: Simplify right side
    709.87x = 391,230.84
  5. Step 5: Solve for x
    x = 391,230.84/709.87
  6. Step 6: Final answer
    x = 551.13

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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.