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Finding the Fourth Proportional to 688.55, 949.92 and 408.68

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Solution

The fourth proportional to 688.55, 949.92 and 408.68 is: 563.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.55 : 949.92 = 408.68 : x
  2. Step 2: Convert to fraction form
    688.55/949.92 = 408.68/x
  3. Step 3: Cross multiply
    688.55x = 949.92 × 408.68
  4. Step 4: Simplify right side
    688.55x = 388,208.56
  5. Step 5: Solve for x
    x = 388,208.56/688.55
  6. Step 6: Final answer
    x = 563.81

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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.