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Finding the Fourth Proportional to 688.34, 949.86 and 408.56

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Solution

The fourth proportional to 688.34, 949.86 and 408.56 is: 563.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.34 : 949.86 = 408.56 : x
  2. Step 2: Convert to fraction form
    688.34/949.86 = 408.56/x
  3. Step 3: Cross multiply
    688.34x = 949.86 × 408.56
  4. Step 4: Simplify right side
    688.34x = 388,074.80
  5. Step 5: Solve for x
    x = 388,074.80/688.34
  6. Step 6: Final answer
    x = 563.78

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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.