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Finding the Fourth Proportional to 687.87, 949.27 and 408.25

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Solution

The fourth proportional to 687.87, 949.27 and 408.25 is: 563.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.87 : 949.27 = 408.25 : x
  2. Step 2: Convert to fraction form
    687.87/949.27 = 408.25/x
  3. Step 3: Cross multiply
    687.87x = 949.27 × 408.25
  4. Step 4: Simplify right side
    687.87x = 387,539.48
  5. Step 5: Solve for x
    x = 387,539.48/687.87
  6. Step 6: Final answer
    x = 563.39

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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.