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Finding the Fourth Proportional to 688.69, 949.97 and 408.74

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Solution

The fourth proportional to 688.69, 949.97 and 408.74 is: 563.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.69 : 949.97 = 408.74 : x
  2. Step 2: Convert to fraction form
    688.69/949.97 = 408.74/x
  3. Step 3: Cross multiply
    688.69x = 949.97 × 408.74
  4. Step 4: Simplify right side
    688.69x = 388,287.01
  5. Step 5: Solve for x
    x = 388,287.01/688.69
  6. Step 6: Final answer
    x = 563.81

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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.