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Finding the Fourth Proportional to 628.86, 868.35 and 408.19

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Solution

The fourth proportional to 628.86, 868.35 and 408.19 is: 563.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.86 : 868.35 = 408.19 : x
  2. Step 2: Convert to fraction form
    628.86/868.35 = 408.19/x
  3. Step 3: Cross multiply
    628.86x = 868.35 × 408.19
  4. Step 4: Simplify right side
    628.86x = 354,452.87
  5. Step 5: Solve for x
    x = 354,452.87/628.86
  6. Step 6: Final answer
    x = 563.64

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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.