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Finding the Fourth Proportional to 688.17, 949.40 and 408.30

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Solution

The fourth proportional to 688.17, 949.40 and 408.30 is: 563.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.17 : 949.40 = 408.30 : x
  2. Step 2: Convert to fraction form
    688.17/949.40 = 408.30/x
  3. Step 3: Cross multiply
    688.17x = 949.40 × 408.30
  4. Step 4: Simplify right side
    688.17x = 387,641.04
  5. Step 5: Solve for x
    x = 387,641.04/688.17
  6. Step 6: Final answer
    x = 563.29

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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.