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Finding the Fourth Proportional to 628.68, 868.09 and 408.00

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Solution

The fourth proportional to 628.68, 868.09 and 408.00 is: 563.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.68 : 868.09 = 408.00 : x
  2. Step 2: Convert to fraction form
    628.68/868.09 = 408.00/x
  3. Step 3: Cross multiply
    628.68x = 868.09 × 408.00
  4. Step 4: Simplify right side
    628.68x = 354,184.49
  5. Step 5: Solve for x
    x = 354,184.49/628.68
  6. Step 6: Final answer
    x = 563.38

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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.