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Finding the Fourth Proportional to 688.19, 949.55 and 408.29

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Solution

The fourth proportional to 688.19, 949.55 and 408.29 is: 563.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.19 : 949.55 = 408.29 : x
  2. Step 2: Convert to fraction form
    688.19/949.55 = 408.29/x
  3. Step 3: Cross multiply
    688.19x = 949.55 × 408.29
  4. Step 4: Simplify right side
    688.19x = 387,688.04
  5. Step 5: Solve for x
    x = 387,688.04/688.19
  6. Step 6: Final answer
    x = 563.34

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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.