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Finding the Fourth Proportional to 708.77, 978.10 and 394.09

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Solution

The fourth proportional to 708.77, 978.10 and 394.09 is: 543.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    708.77 : 978.10 = 394.09 : x
  2. Step 2: Convert to fraction form
    708.77/978.10 = 394.09/x
  3. Step 3: Cross multiply
    708.77x = 978.10 × 394.09
  4. Step 4: Simplify right side
    708.77x = 385,459.43
  5. Step 5: Solve for x
    x = 385,459.43/708.77
  6. Step 6: Final answer
    x = 543.84

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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.